| r0.1 | label_boi_a2/Consolidated | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x10 | boi_CS:x2 | N/A | boi_MU:x1 | boi_RP:x25 |
| r0.2 | label_boi_a2/Company | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x10 | boi_CS:x1 | N/A | boi_MU:x1 | boi_RP:x25 |
| 1.1 | Wages and related/Consolidated | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x10 | boi_CS:x2 | boi_MC:x488 | boi_MU:x1 | boi_RP:x25 |
| 1.2 | Wages and related/Company | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x10 | boi_CS:x1 | boi_MC:x488 | boi_MU:x1 | boi_RP:x25 |
| 2.1 | Advertising/Consolidated | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x10 | boi_CS:x2 | boi_MC:x493 | boi_MU:x1 | boi_RP:x25 |
| 2.2 | Advertising/Company | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x10 | boi_CS:x1 | boi_MC:x493 | boi_MU:x1 | boi_RP:x25 |
| 3.1 | Customer retention and recruitment/Consolidated | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x10 | boi_CS:x2 | boi_MC:x494 | boi_MU:x1 | boi_RP:x25 |
| 3.2 | Customer retention and recruitment/Company | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x10 | boi_CS:x1 | boi_MC:x494 | boi_MU:x1 | boi_RP:x25 |
| 4.1 | Giveaway promotions for credit card holders/Consolidated | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x10 | boi_CS:x2 | boi_MC:x495 | boi_MU:x1 | boi_RP:x25 |
| 4.2 | Giveaway promotions for credit card holders/Company | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x10 | boi_CS:x1 | boi_MC:x495 | boi_MU:x1 | boi_RP:x25 |
| 5.1 | Insurance abroad for credit card holders/Consolidated | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x10 | boi_CS:x2 | boi_MC:x496 | boi_MU:x1 | boi_RP:x25 |
| 5.2 | Insurance abroad for credit card holders/Company | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x10 | boi_CS:x1 | boi_MC:x496 | boi_MU:x1 | boi_RP:x25 |
| 6.1 | Motor vehicle maintenance/Consolidated | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x10 | boi_CS:x2 | boi_MC:x497 | boi_MU:x1 | boi_RP:x25 |
| 6.2 | Motor vehicle maintenance/Company | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x10 | boi_CS:x1 | boi_MC:x497 | boi_MU:x1 | boi_RP:x25 |
| 7.1 | Other/Consolidated | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x10 | boi_CS:x2 | boi_MC:x498 | boi_MU:x1 | boi_RP:x25 |
| 7.2 | Other/Company | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x10 | boi_CS:x1 | boi_MC:x498 | boi_MU:x1 | boi_RP:x25 |
| 8.1 | Total sales and marketing expenses/Consolidated | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x10 | boi_CS:x2 | boi_MC:x459 | boi_MU:x1 | boi_RP:x25 |
| 8.2 | Total sales and marketing expenses/Company | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x10 | boi_CS:x1 | boi_MC:x459 | boi_MU:x1 | boi_RP:x25 |
| 9.1 | Thereof: originating in share-based payment transactions/Consolidated | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x10 | boi_CS:x2 | boi_MC:x489 | boi_MU:x1 | boi_RP:x25 |
| 9.2 | Thereof: originating in share-based payment transactions/Company | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x10 | boi_CS:x1 | boi_MC:x489 | boi_MU:x1 | boi_RP:x25 |
| 10.1 | Thereof: originating in transactions treated as share-based payment transactions, settled bymeans of capital instruments/Consolidated | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x10 | boi_CS:x2 | boi_MC:x490 | boi_MU:x1 | boi_RP:x25 |
| 10.2 | Thereof: originating in transactions treated as share-based payment transactions, settled bymeans of capital instruments/Company | boi_met:md13 | xbrli:monetaryItemType | instant | boi_BC:x10 | boi_CS:x1 | boi_MC:x490 | boi_MU:x1 | boi_RP:x25 |