| r0.1 | label_boi_a2/Balance of Inactive Deposit Accounts | boi_met:mi1 | xbrli:monetaryItemType | instant | boi_BC:x2 | boi_CS:x1 | N/A | boi_MC:x17 | N/A | boi_ST:x201 | N/A |
| r0.2 | label_boi_a2/Number of Inactive Deposit Accounts | boi_met:ii289 | xbrli:integerItemType | instant | boi_BC:x2 | boi_CS:x1 | N/A | boi_MC:x17 | N/A | boi_ST:x201 | N/A |
| r0.3 | label_boi_a2/Balance of Inactive Deposit Accounts | boi_met:mi1 | xbrli:monetaryItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x1 | boi_MC:x17 | boi_SE:x349 | boi_ST:x201 | N/A |
| r0.4 | label_boi_a2/Number of Inactive Deposit Accounts | boi_met:ii289 | xbrli:integerItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x1 | boi_MC:x17 | boi_SE:x349 | boi_ST:x201 | N/A |
| r0.5 | label_boi_a2/Balance of Inactive Deposit Accounts | boi_met:mi1 | xbrli:monetaryItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x1 | boi_MC:x17 | boi_SE:x350 | boi_ST:x201 | N/A |
| r0.6 | label_boi_a2/Number of Inactive Deposit Accounts | boi_met:ii289 | xbrli:integerItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x1 | boi_MC:x17 | boi_SE:x350 | boi_ST:x201 | N/A |
| r0.7 | label_boi_a2/Balance of Inactive Deposit Accounts | boi_met:mi1 | xbrli:monetaryItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x1 | boi_MC:x17 | boi_SE:x358 | boi_ST:x201 | N/A |
| r0.8 | label_boi_a2/Number of Inactive Deposit Accounts | boi_met:ii289 | xbrli:integerItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x1 | boi_MC:x17 | boi_SE:x358 | boi_ST:x201 | N/A |
| r0.9 | label_boi_a2/Balance of Inactive Deposit Accounts | boi_met:mi1 | xbrli:monetaryItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x2 | boi_MC:x17 | boi_SE:x349 | boi_ST:x201 | N/A |
| r0.10 | label_boi_a2/Number of Inactive Deposit Accounts | boi_met:ii289 | xbrli:integerItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x2 | boi_MC:x17 | boi_SE:x349 | boi_ST:x201 | N/A |
| r0.11 | label_boi_a2/Balance of Inactive Deposit Accounts | boi_met:mi1 | xbrli:monetaryItemType | instant | boi_BC:x2 | boi_CS:x1 | N/A | boi_MC:x17 | boi_SE:x351 | boi_ST:x201 | N/A |
| r0.12 | label_boi_a2/Number of Inactive Deposit Accounts | boi_met:ii289 | xbrli:integerItemType | instant | boi_BC:x2 | boi_CS:x1 | N/A | boi_MC:x17 | boi_SE:x351 | boi_ST:x201 | N/A |
| 1.1 | Less than one Year/Balance of Inactive Deposit Accounts | boi_met:mi1 | xbrli:monetaryItemType | instant | boi_BC:x2 | boi_CS:x1 | N/A | boi_MC:x17 | N/A | boi_ST:x201 | boi_TI:x62 |
| 1.2 | Less than one Year/Number of Inactive Deposit Accounts | boi_met:ii289 | xbrli:integerItemType | instant | boi_BC:x2 | boi_CS:x1 | N/A | boi_MC:x17 | N/A | boi_ST:x201 | boi_TI:x62 |
| 1.3 | Less than one Year/Balance of Inactive Deposit Accounts | boi_met:mi1 | xbrli:monetaryItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x1 | boi_MC:x17 | boi_SE:x349 | boi_ST:x201 | boi_TI:x62 |
| 1.4 | Less than one Year/Number of Inactive Deposit Accounts | boi_met:ii289 | xbrli:integerItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x1 | boi_MC:x17 | boi_SE:x349 | boi_ST:x201 | boi_TI:x62 |
| 1.5 | Less than one Year/Balance of Inactive Deposit Accounts | boi_met:mi1 | xbrli:monetaryItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x1 | boi_MC:x17 | boi_SE:x350 | boi_ST:x201 | boi_TI:x62 |
| 1.6 | Less than one Year/Number of Inactive Deposit Accounts | boi_met:ii289 | xbrli:integerItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x1 | boi_MC:x17 | boi_SE:x350 | boi_ST:x201 | boi_TI:x62 |
| 1.7 | Less than one Year/Balance of Inactive Deposit Accounts | boi_met:mi1 | xbrli:monetaryItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x1 | boi_MC:x17 | boi_SE:x358 | boi_ST:x201 | boi_TI:x62 |
| 1.8 | Less than one Year/Number of Inactive Deposit Accounts | boi_met:ii289 | xbrli:integerItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x1 | boi_MC:x17 | boi_SE:x358 | boi_ST:x201 | boi_TI:x62 |
| 1.9 | Less than one Year/Balance of Inactive Deposit Accounts | boi_met:mi1 | xbrli:monetaryItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x2 | boi_MC:x17 | boi_SE:x349 | boi_ST:x201 | boi_TI:x62 |
| 1.10 | Less than one Year/Number of Inactive Deposit Accounts | boi_met:ii289 | xbrli:integerItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x2 | boi_MC:x17 | boi_SE:x349 | boi_ST:x201 | boi_TI:x62 |
| 1.11 | Less than one Year/Balance of Inactive Deposit Accounts | boi_met:mi1 | xbrli:monetaryItemType | instant | boi_BC:x2 | boi_CS:x1 | N/A | boi_MC:x17 | boi_SE:x351 | boi_ST:x201 | boi_TI:x62 |
| 1.12 | Less than one Year/Number of Inactive Deposit Accounts | boi_met:ii289 | xbrli:integerItemType | instant | boi_BC:x2 | boi_CS:x1 | N/A | boi_MC:x17 | boi_SE:x351 | boi_ST:x201 | boi_TI:x62 |
| 2.1 | One to Five Years/Balance of Inactive Deposit Accounts | boi_met:mi1 | xbrli:monetaryItemType | instant | boi_BC:x2 | boi_CS:x1 | N/A | boi_MC:x17 | N/A | boi_ST:x201 | boi_TI:x85 |
| 2.2 | One to Five Years/Number of Inactive Deposit Accounts | boi_met:ii289 | xbrli:integerItemType | instant | boi_BC:x2 | boi_CS:x1 | N/A | boi_MC:x17 | N/A | boi_ST:x201 | boi_TI:x85 |
| 2.3 | One to Five Years/Balance of Inactive Deposit Accounts | boi_met:mi1 | xbrli:monetaryItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x1 | boi_MC:x17 | boi_SE:x349 | boi_ST:x201 | boi_TI:x85 |
| 2.4 | One to Five Years/Number of Inactive Deposit Accounts | boi_met:ii289 | xbrli:integerItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x1 | boi_MC:x17 | boi_SE:x349 | boi_ST:x201 | boi_TI:x85 |
| 2.5 | One to Five Years/Balance of Inactive Deposit Accounts | boi_met:mi1 | xbrli:monetaryItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x1 | boi_MC:x17 | boi_SE:x350 | boi_ST:x201 | boi_TI:x85 |
| 2.6 | One to Five Years/Number of Inactive Deposit Accounts | boi_met:ii289 | xbrli:integerItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x1 | boi_MC:x17 | boi_SE:x350 | boi_ST:x201 | boi_TI:x85 |
| 2.7 | One to Five Years/Balance of Inactive Deposit Accounts | boi_met:mi1 | xbrli:monetaryItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x1 | boi_MC:x17 | boi_SE:x358 | boi_ST:x201 | boi_TI:x85 |
| 2.8 | One to Five Years/Number of Inactive Deposit Accounts | boi_met:ii289 | xbrli:integerItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x1 | boi_MC:x17 | boi_SE:x358 | boi_ST:x201 | boi_TI:x85 |
| 2.9 | One to Five Years/Balance of Inactive Deposit Accounts | boi_met:mi1 | xbrli:monetaryItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x2 | boi_MC:x17 | boi_SE:x349 | boi_ST:x201 | boi_TI:x85 |
| 2.10 | One to Five Years/Number of Inactive Deposit Accounts | boi_met:ii289 | xbrli:integerItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x2 | boi_MC:x17 | boi_SE:x349 | boi_ST:x201 | boi_TI:x85 |
| 2.11 | One to Five Years/Balance of Inactive Deposit Accounts | boi_met:mi1 | xbrli:monetaryItemType | instant | boi_BC:x2 | boi_CS:x1 | N/A | boi_MC:x17 | boi_SE:x351 | boi_ST:x201 | boi_TI:x85 |
| 2.12 | One to Five Years/Number of Inactive Deposit Accounts | boi_met:ii289 | xbrli:integerItemType | instant | boi_BC:x2 | boi_CS:x1 | N/A | boi_MC:x17 | boi_SE:x351 | boi_ST:x201 | boi_TI:x85 |
| 3.1 | Five to Ten Years/Balance of Inactive Deposit Accounts | boi_met:mi1 | xbrli:monetaryItemType | instant | boi_BC:x2 | boi_CS:x1 | N/A | boi_MC:x17 | N/A | boi_ST:x201 | boi_TI:x20 |
| 3.2 | Five to Ten Years/Number of Inactive Deposit Accounts | boi_met:ii289 | xbrli:integerItemType | instant | boi_BC:x2 | boi_CS:x1 | N/A | boi_MC:x17 | N/A | boi_ST:x201 | boi_TI:x20 |
| 3.3 | Five to Ten Years/Balance of Inactive Deposit Accounts | boi_met:mi1 | xbrli:monetaryItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x1 | boi_MC:x17 | boi_SE:x349 | boi_ST:x201 | boi_TI:x20 |
| 3.4 | Five to Ten Years/Number of Inactive Deposit Accounts | boi_met:ii289 | xbrli:integerItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x1 | boi_MC:x17 | boi_SE:x349 | boi_ST:x201 | boi_TI:x20 |
| 3.5 | Five to Ten Years/Balance of Inactive Deposit Accounts | boi_met:mi1 | xbrli:monetaryItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x1 | boi_MC:x17 | boi_SE:x350 | boi_ST:x201 | boi_TI:x20 |
| 3.6 | Five to Ten Years/Number of Inactive Deposit Accounts | boi_met:ii289 | xbrli:integerItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x1 | boi_MC:x17 | boi_SE:x350 | boi_ST:x201 | boi_TI:x20 |
| 3.7 | Five to Ten Years/Balance of Inactive Deposit Accounts | boi_met:mi1 | xbrli:monetaryItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x1 | boi_MC:x17 | boi_SE:x358 | boi_ST:x201 | boi_TI:x20 |
| 3.8 | Five to Ten Years/Number of Inactive Deposit Accounts | boi_met:ii289 | xbrli:integerItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x1 | boi_MC:x17 | boi_SE:x358 | boi_ST:x201 | boi_TI:x20 |
| 3.9 | Five to Ten Years/Balance of Inactive Deposit Accounts | boi_met:mi1 | xbrli:monetaryItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x2 | boi_MC:x17 | boi_SE:x349 | boi_ST:x201 | boi_TI:x20 |
| 3.10 | Five to Ten Years/Number of Inactive Deposit Accounts | boi_met:ii289 | xbrli:integerItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x2 | boi_MC:x17 | boi_SE:x349 | boi_ST:x201 | boi_TI:x20 |
| 3.11 | Five to Ten Years/Balance of Inactive Deposit Accounts | boi_met:mi1 | xbrli:monetaryItemType | instant | boi_BC:x2 | boi_CS:x1 | N/A | boi_MC:x17 | boi_SE:x351 | boi_ST:x201 | boi_TI:x20 |
| 3.12 | Five to Ten Years/Number of Inactive Deposit Accounts | boi_met:ii289 | xbrli:integerItemType | instant | boi_BC:x2 | boi_CS:x1 | N/A | boi_MC:x17 | boi_SE:x351 | boi_ST:x201 | boi_TI:x20 |
| 4.1 | Over Ten Years/Balance of Inactive Deposit Accounts | boi_met:mi1 | xbrli:monetaryItemType | instant | boi_BC:x2 | boi_CS:x1 | N/A | boi_MC:x17 | N/A | boi_ST:x201 | boi_TI:x78 |
| 4.2 | Over Ten Years/Number of Inactive Deposit Accounts | boi_met:ii289 | xbrli:integerItemType | instant | boi_BC:x2 | boi_CS:x1 | N/A | boi_MC:x17 | N/A | boi_ST:x201 | boi_TI:x78 |
| 4.3 | Over Ten Years/Balance of Inactive Deposit Accounts | boi_met:mi1 | xbrli:monetaryItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x1 | boi_MC:x17 | boi_SE:x349 | boi_ST:x201 | boi_TI:x78 |
| 4.4 | Over Ten Years/Number of Inactive Deposit Accounts | boi_met:ii289 | xbrli:integerItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x1 | boi_MC:x17 | boi_SE:x349 | boi_ST:x201 | boi_TI:x78 |
| 4.5 | Over Ten Years/Balance of Inactive Deposit Accounts | boi_met:mi1 | xbrli:monetaryItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x1 | boi_MC:x17 | boi_SE:x350 | boi_ST:x201 | boi_TI:x78 |
| 4.6 | Over Ten Years/Number of Inactive Deposit Accounts | boi_met:ii289 | xbrli:integerItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x1 | boi_MC:x17 | boi_SE:x350 | boi_ST:x201 | boi_TI:x78 |
| 4.7 | Over Ten Years/Balance of Inactive Deposit Accounts | boi_met:mi1 | xbrli:monetaryItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x1 | boi_MC:x17 | boi_SE:x358 | boi_ST:x201 | boi_TI:x78 |
| 4.8 | Over Ten Years/Number of Inactive Deposit Accounts | boi_met:ii289 | xbrli:integerItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x1 | boi_MC:x17 | boi_SE:x358 | boi_ST:x201 | boi_TI:x78 |
| 4.9 | Over Ten Years/Balance of Inactive Deposit Accounts | boi_met:mi1 | xbrli:monetaryItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x2 | boi_MC:x17 | boi_SE:x349 | boi_ST:x201 | boi_TI:x78 |
| 4.10 | Over Ten Years/Number of Inactive Deposit Accounts | boi_met:ii289 | xbrli:integerItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x2 | boi_MC:x17 | boi_SE:x349 | boi_ST:x201 | boi_TI:x78 |
| 4.11 | Over Ten Years/Balance of Inactive Deposit Accounts | boi_met:mi1 | xbrli:monetaryItemType | instant | boi_BC:x2 | boi_CS:x1 | N/A | boi_MC:x17 | boi_SE:x351 | boi_ST:x201 | boi_TI:x78 |
| 4.12 | Over Ten Years/Number of Inactive Deposit Accounts | boi_met:ii289 | xbrli:integerItemType | instant | boi_BC:x2 | boi_CS:x1 | N/A | boi_MC:x17 | boi_SE:x351 | boi_ST:x201 | boi_TI:x78 |
| 5.1 | Total/Balance of Inactive Deposit Accounts | boi_met:mi1 | xbrli:monetaryItemType | instant | boi_BC:x2 | boi_CS:x1 | N/A | boi_MC:x17 | N/A | boi_ST:x201 | N/A |
| 5.2 | Total/Number of Inactive Deposit Accounts | boi_met:ii289 | xbrli:integerItemType | instant | boi_BC:x2 | boi_CS:x1 | N/A | boi_MC:x17 | N/A | boi_ST:x201 | N/A |
| 5.3 | Total/Balance of Inactive Deposit Accounts | boi_met:mi1 | xbrli:monetaryItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x1 | boi_MC:x17 | boi_SE:x349 | boi_ST:x201 | N/A |
| 5.4 | Total/Number of Inactive Deposit Accounts | boi_met:ii289 | xbrli:integerItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x1 | boi_MC:x17 | boi_SE:x349 | boi_ST:x201 | N/A |
| 5.5 | Total/Balance of Inactive Deposit Accounts | boi_met:mi1 | xbrli:monetaryItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x1 | boi_MC:x17 | boi_SE:x350 | boi_ST:x201 | N/A |
| 5.6 | Total/Number of Inactive Deposit Accounts | boi_met:ii289 | xbrli:integerItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x1 | boi_MC:x17 | boi_SE:x350 | boi_ST:x201 | N/A |
| 5.7 | Total/Balance of Inactive Deposit Accounts | boi_met:mi1 | xbrli:monetaryItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x1 | boi_MC:x17 | boi_SE:x358 | boi_ST:x201 | N/A |
| 5.8 | Total/Number of Inactive Deposit Accounts | boi_met:ii289 | xbrli:integerItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x1 | boi_MC:x17 | boi_SE:x358 | boi_ST:x201 | N/A |
| 5.9 | Total/Balance of Inactive Deposit Accounts | boi_met:mi1 | xbrli:monetaryItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x2 | boi_MC:x17 | boi_SE:x349 | boi_ST:x201 | N/A |
| 5.10 | Total/Number of Inactive Deposit Accounts | boi_met:ii289 | xbrli:integerItemType | instant | boi_BC:x2 | boi_CS:x1 | boi_GA:x2 | boi_MC:x17 | boi_SE:x349 | boi_ST:x201 | N/A |
| 5.11 | Total/Balance of Inactive Deposit Accounts | boi_met:mi1 | xbrli:monetaryItemType | instant | boi_BC:x2 | boi_CS:x1 | N/A | boi_MC:x17 | boi_SE:x351 | boi_ST:x201 | N/A |
| 5.12 | Total/Number of Inactive Deposit Accounts | boi_met:ii289 | xbrli:integerItemType | instant | boi_BC:x2 | boi_CS:x1 | N/A | boi_MC:x17 | boi_SE:x351 | boi_ST:x201 | N/A |