REGULATORY CAPITAL (Summary of actual capital amounts and ratios) (Details) $ in Thousands	12 Months Ended
Dec. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)
REGULATORY CAPITAL
Percentage of capital conversion buffer	0.043%	0.053%
Tier 1 leverage ratio (to average assets), Actual Amount	$ 793,738	$ 793,847
Tier 1 leverage ratio (to average assets), Actual Ratio	0.095	0.108
Tier 1 leverage ratio (to average assets), For Capital Adequacy Amount	$ 333,936	$ 294,141
Tier 1 leverage ratio (to average assets), For Capital Adequacy Ratio	0.04	0.04
Tier 1 common equity (to risk-weighted assets), Actual Amount	$ 773,118	$ 773,227
Tier 1 common equity (to risk-weighted assets), Actual Ratio	0.107	0.119
Tier 1 common equity (to risk-weighted assets), For Capital Adequacy Amount	$ 324,706	$ 291,450
Tier 1 common equity (to risk-weighted assets), For Capital Adequacy Ratio	0.045	0.045
Tier 1 common equity (to risk-weighted assets), Minimum Capital Conservation Buffer	0.025	0.025
Tier 1 capital (to risk-weighted assets), Actual Amount	$ 793,738	$ 793,847
Tier 1 capital (to risk-weighted assets), Actual Ratio	0.11	0.123
Tier 1 capital (to risk-weighted assets), For Capital Adequacy Amount	$ 432,941	$ 388,600
Tier 1 capital (to risk-weighted assets), For Capital Adequacy Ratio	0.06	0.06
Tier 1 capital (to risk-weighted assets), Minimum Capital Conservation Buffer	0.025	0.025
Total capital (to risk-weighted assets), Actual Amount	$ 884,046	$ 859,129
Total capital (to risk-weighted assets), Actual Ratio	0.123	0.133
Total capital (to risk-weighted assets), For Capital Adequacy Amount	$ 577,255	$ 518,134
Total capital (to risk-weighted assets), For Capital Adequacy Ratio	0.08	0.08
Total capital (to risk-weighted assets), Minimum Capital Conservation Buffer	0.025	0.025
Metropolitan Commercial Bank
REGULATORY CAPITAL
Percentage of capital conversion buffer	0.037%	0.05%
Tier 1 leverage ratio (to average assets), Actual Amount	$ 756,729	$ 775,106
Tier 1 leverage ratio (to average assets), Actual Ratio	0.091	0.106
Tier 1 leverage ratio (to average assets), For Capital Adequacy Amount	$ 334,012	$ 293,513
Tier 1 leverage ratio (to average assets), For Capital Adequacy Ratio	0.04	0.04
Tier 1 leverage ratio (to average assets), To be Well Capitalized under Prompt Corrective Action Regulations Amount	$ 417,514	$ 366,892
Tier 1 leverage ratio (to average assets), To be Well Capitalized under Prompt Corrective Action Regulations Ratio	0.05	0.05
Tier 1 common equity (to risk-weighted assets), Actual Amount	$ 756,729	$ 775,106
Tier 1 common equity (to risk-weighted assets), Actual Ratio	0.105	0.12
Tier 1 common equity (to risk-weighted assets), For Capital Adequacy Amount	$ 324,676	$ 291,421
Tier 1 common equity (to risk-weighted assets), For Capital Adequacy Ratio	0.045	0.045
Tier 1 common equity (to risk-weighted assets), To be Well Capitalized under Prompt Corrective Action Regulations Amount	$ 468,976	$ 420,942
Tier 1 common equity (to risk-weighted assets), To be Well Capitalized under Prompt Corrective Action Regulations Ratio	0.065	0.065
Tier 1 common equity (to risk-weighted assets), Minimum Capital Conservation Buffer	0.025	0.025
Tier 1 capital (to risk-weighted assets), Actual Amount	$ 756,729	$ 775,106
Tier 1 capital (to risk-weighted assets), Actual Ratio	0.105	0.12
Tier 1 capital (to risk-weighted assets), For Capital Adequacy Amount	$ 432,901	$ 388,562
Tier 1 capital (to risk-weighted assets), For Capital Adequacy Ratio	0.06	0.06
Tier 1 capital (to risk-weighted assets), To be Well Capitalized under Prompt Corrective Action Regulations Amount	$ 577,202	$ 518,082
Tier 1 capital (to risk-weighted assets), To be Well Capitalized under Prompt Corrective Action Regulations Ratio	0.08	0.08
Tier 1 capital (to risk-weighted assets), Minimum Capital Conservation Buffer	0.025	0.025
Total capital (to risk-weighted assets), Actual Amount	$ 847,028	$ 840,387
Total capital (to risk-weighted assets), Actual Ratio	0.117	0.13
Total capital (to risk-weighted assets), For Capital Adequacy Amount	$ 577,202	$ 518,082
Total capital (to risk-weighted assets), For Capital Adequacy Ratio	0.08	0.08
Total capital (to risk-weighted assets), To be Well Capitalized under Prompt Corrective Action Regulations Amount	$ 721,502	$ 647,603
Total capital (to risk-weighted assets), To be Well Capitalized under Prompt Corrective Action Regulations Ratio	0.10	0.10
Total capital (to risk-weighted assets), Minimum Capital Conservation Buffer	0.025	0.025

Percentage of common equity tier one capital required for capital adequacy to risk weighted assets ratio.

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Percentage of capital conversion buffer as at the end of the reporting period.

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Amount of minimum total risk-based capital required for capital adequacy as defined by regulatory framework.

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