| r0.1 | label_boi_a2/Consolidated | | | | N/A | N/A | boi_CS:x2 | N/A | boi_MU:x1 | boi_RP:x25 |
| r0.2 | label_boi_a2/Bank | | | | N/A | N/A | boi_CS:x1 | N/A | boi_MU:x1 | boi_RP:x25 |
| 1.1 | Intrest income/Consolidated | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x9 | N/A | boi_CS:x2 | boi_MC:x125 | boi_MU:x1 | boi_RP:x25 |
| 1.2 | Intrest income/Bank | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x9 | N/A | boi_CS:x1 | boi_MC:x125 | boi_MU:x1 | boi_RP:x25 |
| 2.1 | Intrest expenses/Consolidated | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x10 | N/A | boi_CS:x2 | boi_MC:x125 | boi_MU:x1 | boi_RP:x25 |
| 2.2 | Intrest expenses/Bank | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x10 | N/A | boi_CS:x1 | boi_MC:x125 | boi_MU:x1 | boi_RP:x25 |
| 3.1 | Net Intrest income/Consolidated | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x11 | N/A | boi_CS:x2 | boi_MC:x125 | boi_MU:x1 | boi_RP:x25 |
| 3.2 | Net Intrest income/Bank | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x11 | N/A | boi_CS:x1 | boi_MC:x125 | boi_MU:x1 | boi_RP:x25 |
| 4.1 | Expenses in respect of credit losses/Consolidated | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x12 | N/A | boi_CS:x2 | boi_MC:x126 | boi_MU:x1 | boi_RP:x25 |
| 4.2 | Expenses in respect of credit losses/Bank | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x12 | N/A | boi_CS:x1 | boi_MC:x126 | boi_MU:x1 | boi_RP:x25 |
| 5.1 | Net Intrest income after expenses in respect of credit losses/Consolidated | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x11 | N/A | boi_CS:x2 | boi_MC:x124 | boi_MU:x1 | boi_RP:x25 |
| 5.2 | Net Intrest income after expenses in respect of credit losses/Bank | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x11 | N/A | boi_CS:x1 | boi_MC:x124 | boi_MU:x1 | boi_RP:x25 |
| r6.1 | Non-interest income/Consolidated | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x11 | N/A | boi_CS:x2 | N/A | boi_MU:x1 | boi_RP:x25 |
| r6.2 | Non-interest income/Bank | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x11 | N/A | boi_CS:x1 | N/A | boi_MU:x1 | boi_RP:x25 |
| 6.1 | Non-interest financing income/Consolidated | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x11 | N/A | boi_CS:x2 | boi_MC:x128 | boi_MU:x1 | boi_RP:x25 |
| 6.2 | Non-interest financing income/Bank | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x11 | N/A | boi_CS:x1 | boi_MC:x128 | boi_MU:x1 | boi_RP:x25 |
| 7.1 | Fees/Consolidated | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x11 | N/A | boi_CS:x2 | boi_MC:x141 | boi_MU:x1 | boi_RP:x25 |
| 7.2 | Fees/Bank | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x11 | N/A | boi_CS:x1 | boi_MC:x141 | boi_MU:x1 | boi_RP:x25 |
| 8.1 | Other income/Consolidated | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x11 | N/A | boi_CS:x2 | boi_MC:x153 | boi_MU:x1 | boi_RP:x25 |
| 8.2 | Other income/Bank | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x11 | N/A | boi_CS:x1 | boi_MC:x153 | boi_MU:x1 | boi_RP:x25 |
| 9.1 | Non interest total income/Consolidated | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x11 | N/A | boi_CS:x2 | boi_MC:x127 | boi_MU:x1 | boi_RP:x25 |
| 9.2 | Non interest total income/Bank | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x11 | N/A | boi_CS:x1 | boi_MC:x127 | boi_MU:x1 | boi_RP:x25 |
| r11.1 | Operating and other expenses:/Consolidated | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x10 | N/A | boi_CS:x2 | N/A | boi_MU:x1 | boi_RP:x25 |
| r11.2 | Operating and other expenses:/Bank | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x10 | N/A | boi_CS:x1 | N/A | boi_MU:x1 | boi_RP:x25 |
| 10.1 | Salaries and related expences/Consolidated | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x10 | N/A | boi_CS:x2 | boi_MC:x161 | boi_MU:x1 | boi_RP:x25 |
| 10.2 | Salaries and related expences/Bank | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x10 | N/A | boi_CS:x1 | boi_MC:x161 | boi_MU:x1 | boi_RP:x25 |
| 11.1 | Maintenance and depreciation on building and equipment/Consolidated | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x10 | N/A | boi_CS:x2 | boi_MC:x171 | boi_MU:x1 | boi_RP:x25 |
| 11.2 | Maintenance and depreciation on building and equipment/Bank | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x10 | N/A | boi_CS:x1 | boi_MC:x171 | boi_MU:x1 | boi_RP:x25 |
| 12.1 | Amortisations and impairments of intangible assets and goodwill/Consolidated | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x10 | N/A | boi_CS:x2 | boi_MC:x172 | boi_MU:x1 | boi_RP:x25 |
| 12.2 | Amortisations and impairments of intangible assets and goodwill/Bank | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x10 | N/A | boi_CS:x1 | boi_MC:x172 | boi_MU:x1 | boi_RP:x25 |
| 13.1 | Other expences/Consolidated | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x10 | N/A | boi_CS:x2 | boi_MC:x173 | boi_MU:x1 | boi_RP:x25 |
| 13.2 | Other expences/Bank | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x10 | N/A | boi_CS:x1 | boi_MC:x173 | boi_MU:x1 | boi_RP:x25 |
| 14.1 | Total/Consolidated | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x10 | N/A | boi_CS:x2 | boi_MC:x160 | boi_MU:x1 | boi_RP:x25 |
| 14.2 | Total/Bank | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x10 | N/A | boi_CS:x1 | boi_MC:x160 | boi_MU:x1 | boi_RP:x25 |
| 15.1 | Profit before taxes/Consolidated | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x11 | N/A | boi_CS:x2 | boi_MC:x123 | boi_MU:x1 | boi_RP:x25 |
| 15.2 | Profit before taxes/Bank | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x11 | N/A | boi_CS:x1 | boi_MC:x123 | boi_MU:x1 | boi_RP:x25 |
| 16.1 | Provision for taxes on profit/Consolidated | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x12 | N/A | boi_CS:x2 | boi_MC:x190 | boi_MU:x1 | boi_RP:x25 |
| 16.2 | Provision for taxes on profit/Bank | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x12 | N/A | boi_CS:x1 | boi_MC:x190 | boi_MU:x1 | boi_RP:x25 |
| 17.1 | Profit after taxes/Consolidated | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x11 | N/A | boi_CS:x2 | boi_MC:x122 | boi_MU:x1 | boi_RP:x25 |
| 17.2 | Profit after taxes/Bank | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x11 | N/A | boi_CS:x1 | boi_MC:x122 | boi_MU:x1 | boi_RP:x25 |
| 18.1 | Share of reporting office in profit of companies included on equity basis after the effect of taxes/Consolidated | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x11 | N/A | boi_CS:x2 | boi_MC:x191 | boi_MU:x1 | boi_RP:x25 |
| 18.2 | Share of reporting office in profit of companies included on equity basis after the effect of taxes/Bank | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x11 | N/A | boi_CS:x1 | boi_MC:x191 | boi_MU:x1 | boi_RP:x25 |
| r21.1 | Net profit/Consolidated | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x11 | N/A | boi_CS:x2 | boi_MC:x121 | boi_MU:x1 | boi_RP:x25 |
| r21.2 | Net profit/Bank | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x11 | N/A | boi_CS:x1 | boi_MC:x121 | boi_MU:x1 | boi_RP:x25 |
| 19.1 | Net profit: Before attributed to holders of noncontrolling interest/Consolidated | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x11 | N/A | boi_CS:x2 | boi_MC:x121 | boi_MU:x1 | boi_RP:x25 |
| 19.2 | Net profit: Before attributed to holders of noncontrolling interest/Bank | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x11 | N/A | boi_CS:x1 | boi_MC:x121 | boi_MU:x1 | boi_RP:x25 |
| 20.1 | Attributed to holders of noncontrolling interest/Consolidated | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x11 | boi_CN:x2 | boi_CS:x2 | boi_MC:x121 | boi_MU:x1 | boi_RP:x25 |
| 20.2 | Attributed to holders of noncontrolling interest/Bank | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x11 | boi_CN:x2 | boi_CS:x1 | boi_MC:x121 | boi_MU:x1 | boi_RP:x25 |
| 21.1 | Net profit attributed to shareholders of the banking corporation/Consolidated | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x11 | boi_CN:x1 | boi_CS:x2 | boi_MC:x121 | boi_MU:x1 | boi_RP:x25 |
| 21.2 | Net profit attributed to shareholders of the banking corporation/Bank | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x11 | boi_CN:x1 | boi_CS:x1 | boi_MC:x121 | boi_MU:x1 | boi_RP:x25 |
| 22.1 | Basic earnings: Net profit attributable to shareholders of the bank/Consolidated | boi_met:md81 | xbrli:monetaryItemType | instant | boi_BC:x11 | boi_CN:x1 | boi_CS:x2 | boi_MC:x121 | boi_MU:x1 | boi_RP:x25 |
| 22.2 | Basic earnings: Net profit attributable to shareholders of the bank/Bank | boi_met:md81 | xbrli:monetaryItemType | instant | boi_BC:x11 | boi_CN:x1 | boi_CS:x1 | boi_MC:x121 | boi_MU:x1 | boi_RP:x25 |
| 23.1 | Diluted earnings: Net income attributable to shareholders of the bank/Consolidated | boi_met:md82 | xbrli:monetaryItemType | instant | boi_BC:x11 | boi_CN:x1 | boi_CS:x2 | boi_MC:x121 | boi_MU:x1 | boi_RP:x25 |
| 23.2 | Diluted earnings: Net income attributable to shareholders of the bank/Bank | boi_met:md82 | xbrli:monetaryItemType | instant | boi_BC:x11 | boi_CN:x1 | boi_CS:x1 | boi_MC:x121 | boi_MU:x1 | boi_RP:x25 |