| r0.1 | label_boi_a2/No. of contracts | boi_met:id102 | xbrli:integerItemType | instant | boi_BC:x1 | N/A | boi_CS:x2 | N/A | boi_MU:x1 | boi_RP:x3 | N/A | boi_ST:x3 | boi_ST:x41 |
| r0.2 | label_boi_a2/Recorded debt balance | boi_met:md183 | xbrli:monetaryItemType | instant | boi_BC:x1 | N/A | boi_CS:x2 | N/A | boi_MU:x1 | boi_RP:x3 | N/A | boi_ST:x3 | boi_ST:x41 |
| r1.1 | Debts not guaranteed by banks/No. of contracts | boi_met:id102 | xbrli:integerItemType | instant | boi_BC:x1 | boi_CL:x2 | boi_CS:x2 | N/A | boi_MU:x1 | boi_RP:x3 | N/A | boi_ST:x3 | boi_ST:x41 |
| r1.2 | Debts not guaranteed by banks/Recorded debt balance | boi_met:md183 | xbrli:monetaryItemType | instant | boi_BC:x1 | boi_CL:x2 | boi_CS:x2 | N/A | boi_MU:x1 | boi_RP:x3 | N/A | boi_ST:x3 | boi_ST:x41 |
| r2.1 | Private individuals/No. of contracts | boi_met:id102 | xbrli:integerItemType | instant | boi_BC:x1 | boi_CL:x2 | boi_CS:x2 | N/A | boi_MU:x1 | boi_RP:x3 | boi_SE:x15 | boi_ST:x3 | boi_ST:x41 |
| r2.2 | Private individuals/Recorded debt balance | boi_met:md183 | xbrli:monetaryItemType | instant | boi_BC:x1 | boi_CL:x2 | boi_CS:x2 | N/A | boi_MU:x1 | boi_RP:x3 | boi_SE:x15 | boi_ST:x3 | boi_ST:x41 |
| 1.1 | Receivables in respect of credit cards/No. of contracts | boi_met:id102 | xbrli:integerItemType | instant | boi_BC:x1 | boi_CL:x2 | boi_CS:x2 | boi_MC:x143 | boi_MU:x1 | boi_RP:x3 | boi_SE:x15 | boi_ST:x3 | boi_ST:x41 |
| 1.2 | Receivables in respect of credit cards/Recorded debt balance | boi_met:md183 | xbrli:monetaryItemType | instant | boi_BC:x1 | boi_CL:x2 | boi_CS:x2 | boi_MC:x143 | boi_MU:x1 | boi_RP:x3 | boi_SE:x15 | boi_ST:x3 | boi_ST:x41 |
| 2.1 | Credit/No. of contracts | boi_met:id102 | xbrli:integerItemType | instant | boi_BC:x1 | boi_CL:x2 | boi_CS:x2 | boi_MC:x880 | boi_MU:x1 | boi_RP:x3 | boi_SE:x15 | boi_ST:x3 | boi_ST:x41 |
| 2.2 | Credit/Recorded debt balance | boi_met:md183 | xbrli:monetaryItemType | instant | boi_BC:x1 | boi_CL:x2 | boi_CS:x2 | boi_MC:x880 | boi_MU:x1 | boi_RP:x3 | boi_SE:x15 | boi_ST:x3 | boi_ST:x41 |
| r5.1 | Commercial/No. of contracts | boi_met:id102 | xbrli:integerItemType | instant | boi_BC:x1 | boi_CL:x2 | boi_CS:x2 | N/A | boi_MU:x1 | boi_RP:x3 | boi_SE:x4 | boi_ST:x3 | boi_ST:x41 |
| r5.2 | Commercial/Recorded debt balance | boi_met:md183 | xbrli:monetaryItemType | instant | boi_BC:x1 | boi_CL:x2 | boi_CS:x2 | N/A | boi_MU:x1 | boi_RP:x3 | boi_SE:x4 | boi_ST:x3 | boi_ST:x41 |
| 3.1 | Receivables in respect of credit cards/No. of contracts | boi_met:id102 | xbrli:integerItemType | instant | boi_BC:x1 | boi_CL:x2 | boi_CS:x2 | boi_MC:x143 | boi_MU:x1 | boi_RP:x3 | boi_SE:x4 | boi_ST:x3 | boi_ST:x41 |
| 3.2 | Receivables in respect of credit cards/Recorded debt balance | boi_met:md183 | xbrli:monetaryItemType | instant | boi_BC:x1 | boi_CL:x2 | boi_CS:x2 | boi_MC:x143 | boi_MU:x1 | boi_RP:x3 | boi_SE:x4 | boi_ST:x3 | boi_ST:x41 |
| 4.1 | Credit/No. of contracts | boi_met:id102 | xbrli:integerItemType | instant | boi_BC:x1 | boi_CL:x2 | boi_CS:x2 | boi_MC:x880 | boi_MU:x1 | boi_RP:x3 | boi_SE:x4 | boi_ST:x3 | boi_ST:x41 |
| 4.2 | Credit/Recorded debt balance | boi_met:md183 | xbrli:monetaryItemType | instant | boi_BC:x1 | boi_CL:x2 | boi_CS:x2 | boi_MC:x880 | boi_MU:x1 | boi_RP:x3 | boi_SE:x4 | boi_ST:x3 | boi_ST:x41 |
| 5.1 | Total debts not guaranteed by banks/No. of contracts | boi_met:id102 | xbrli:integerItemType | instant | boi_BC:x1 | boi_CL:x2 | boi_CS:x2 | boi_MC:x8 | boi_MU:x1 | boi_RP:x3 | N/A | boi_ST:x3 | boi_ST:x41 |
| 5.2 | Total debts not guaranteed by banks/Recorded debt balance | boi_met:md183 | xbrli:monetaryItemType | instant | boi_BC:x1 | boi_CL:x2 | boi_CS:x2 | boi_MC:x8 | boi_MU:x1 | boi_RP:x3 | N/A | boi_ST:x3 | boi_ST:x41 |
| 6.1 | Debts guaranteed by banks and others/No. of contracts | boi_met:id102 | xbrli:integerItemType | instant | boi_BC:x1 | boi_CL:x40 | boi_CS:x2 | boi_MC:x8 | boi_MU:x1 | boi_RP:x3 | N/A | boi_ST:x3 | boi_ST:x41 |
| 6.2 | Debts guaranteed by banks and others/Recorded debt balance | boi_met:md183 | xbrli:monetaryItemType | instant | boi_BC:x1 | boi_CL:x40 | boi_CS:x2 | boi_MC:x8 | boi_MU:x1 | boi_RP:x3 | N/A | boi_ST:x3 | boi_ST:x41 |
| 7.1 | Total/No. of contracts | boi_met:id102 | xbrli:integerItemType | instant | boi_BC:x1 | N/A | boi_CS:x2 | boi_MC:x8 | boi_MU:x1 | boi_RP:x3 | N/A | boi_ST:x3 | boi_ST:x41 |
| 7.2 | Total/Recorded debt balance | boi_met:md183 | xbrli:monetaryItemType | instant | boi_BC:x1 | N/A | boi_CS:x2 | boi_MC:x8 | boi_MU:x1 | boi_RP:x3 | N/A | boi_ST:x3 | boi_ST:x41 |