Regulatory Capital Requirements (Details) $ in Thousands	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Group [Member]
Capital [Abstract]
Actual - Total capital	$ 1,096,766	$ 937,962
Actual - Tier 1 capital	1,010,945	852,311
Actual -Common equity tier 1 capital	894,075	735,441
Actual - Tier 1 leverage capital	1,010,945	852,311
Minimum Capital - Total Capital	717,974	707,789
Minimum capital - Tier 1 capital	581,217	572,972
Minimum capital - Common equity tier 1 capital	478,649	471,859
Minimum capital - Tier 1 leverage capital	392,424	369,151
Minimum to be well capitalized - Total Capital	683,785	674,085
Minimum to be well capitalized - Tier 1 capital	547,028	539,268
Minimum to be well capitalized - Common equity tier 1 capital	444,460	438,155
Minimum to be well capitalized - Tier 1 leverage	$ 490,530	$ 461,438
Risk Based Ratios [Abstract]
Capital to Risk Weighted Assets	0.1604	0.1391
Tier One Risk Based Capital to Risk Weighted Assets	0.1478	0.1264
Common Equity Tier One To Risk Weighted Assets	13.08%	10.91%
Tier One Leverage Capital to Average Assets	0.1030	0.0924
Capital Required for Capital Adequacy to Risk Weighted Assets	0.1050	0.1050
Tier One Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets	0.0850	0.0850
Common Equity Tier One Required For Capital Adequacy To Risk Weighted Assets	7.00%	7.00%
Tier One Leverage Capital Required for Capital Adequacy to Average Assets	0.0400	0.0400
Capital Required to be Well Capitalized to Risk Weighted Assets	0.1000	0.1000
Tier One Risk Based Capital Required To Be Well Capitalized To Risk Weighted Assets	0.0800	0.0800
Tier One Risk Common Equity Tier One Required To Be Well Capitalized To Risk Weighted Assets	6.50%	6.50%
Tier One Leverage Capital Required to be Well Capitalized to Average Assets	0.0500	0.0500
Bank [Member]
Capital [Abstract]
Actual - Total capital	$ 1,044,275	$ 898,812
Actual - Tier 1 capital	786,731	813,444
Actual -Common equity tier 1 capital	956,845	813,444
Actual - Tier 1 leverage capital	956,845	813,444
Minimum Capital - Total Capital	714,480	706,800
Minimum capital - Tier 1 capital	578,388	572,230
Minimum capital - Common equity tier 1 capital	476,320	471,303
Minimum capital - Tier 1 leverage capital	390,304	367,537
Minimum to be well capitalized - Total Capital	680,457	672,848
Minimum to be well capitalized - Tier 1 capital	544,366	538,279
Minimum to be well capitalized - Common equity tier 1 capital	442,297	437,351
Minimum to be well capitalized - Tier 1 leverage	$ 487,879	$ 459,421
Risk Based Ratios [Abstract]
Capital to Risk Weighted Assets	0.1532	0.1336
Tier One Risk Based Capital to Risk Weighted Assets	0.1406	0.1209
Common Equity Tier One To Risk Weighted Assets	14.06%	12.09%
Tier One Leverage Capital to Average Assets	0.0981	0.0885
Capital Required for Capital Adequacy to Risk Weighted Assets	0.1050	0.1050
Tier One Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets	0.0850	0.0850
Common Equity Tier One Required For Capital Adequacy To Risk Weighted Assets	7.00%	7.00%
Tier One Leverage Capital Required for Capital Adequacy to Average Assets	0.0400	0.0400
Capital Required to be Well Capitalized to Risk Weighted Assets	0.1000	0.1000
Tier One Risk Based Capital Required To Be Well Capitalized To Risk Weighted Assets	0.0800	0.0800
Tier One Risk Common Equity Tier One Required To Be Well Capitalized To Risk Weighted Assets	6.50%	6.50%
Tier One Leverage Capital Required to be Well Capitalized to Average Assets	0.0500	0.0500

The common equity tier 1 capital ratio as defined in the new regulatory framework.

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The amount of Comon Equity Tier 1 required to be categorized as well capitalized under the new regulatory framework.

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The minimum Common Equity Tier One Capital Ratio (Common Equity Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the new regulatory framework.

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Common Equity Tier 1 to Risk Weighted Assets (Common Equity Tier 1 divided by risk weighted assets) as defined by regulations.

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The minimum amount of Common Equity Tier 1 required for capital adequacy purposes under the new regulatory framework.

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Amount of total capital as defined by regulatory framework.

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

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Amount of minimum total risk-based capital categorized as well capitalized as defined by regulatory framework for prompt corrective action.

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Amount of Tier 1 leverage capital as defined by regulatory framework.

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Amount of minimum Tier 1 leverage capital required for capital adequacy as defined by regulatory framework.

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Amount of Tier 1 risk-based capital as defined by regulatory framework.

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