Regulatory Capital Requirements (Details) $ in Thousands	Jun. 30, 2021 USD ($)	Dec. 31, 2020 USD ($)
Group [Member]
Capital [Abstract]
Actual - Total capital	$ 1,094,786	$ 1,096,766
Actual - Tier 1 capital	1,008,785	1,010,945
Actual -Common equity tier 1 capital	957,238	894,075
Actual - Tier 1 leverage capital	1,008,785	1,010,945
Minimum Capital - Total Capital	720,498	717,974
Minimum capital - Tier 1 capital	583,261	581,217
Minimum capital - Common equity tier 1 capital	480,332	478,649
Minimum capital - Tier 1 leverage capital	409,975	392,424
Minimum to be well capitalized - Total Capital	686,189	683,785
Minimum to be well capitalized - Tier 1 capital	548,951	547,028
Minimum to be well capitalized - Common equity tier 1 capital	446,023	444,460
Minimum to be well capitalized - Tier 1 leverage	$ 512,469	$ 490,530
Risk Based Ratios [Abstract]
Capital to Risk Weighted Assets	0.1595	0.1604
Tier One Risk Based Capital to Risk Weighted Assets	0.1470	0.1478
Common Equity Tier OneTo Risk Weighted Assets	13.95%	13.08%
Tier One Leverage Capital to Average Assets	0.0984	0.1030
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	$ 993,250	$ 1,044,275
Actual - Tier 1 capital	907,851	786,731
Actual -Common equity tier 1 capital	907,851	956,845
Actual - Tier 1 leverage capital	907,851	956,845
Minimum Capital - Total Capital	715,375	714,480
Minimum capital - Tier 1 capital	579,113	578,388
Minimum capital - Common equity tier 1 capital	476,917	476,320
Minimum capital - Tier 1 leverage capital	405,219	390,304
Minimum to be well capitalized - Total Capital	681,310	680,457
Minimum to be well capitalized - Tier 1 capital	545,048	544,366
Minimum to be well capitalized - Common equity tier 1 capital	442,851	442,297
Minimum to be well capitalized - Tier 1 leverage	$ 506,524	$ 487,879
Risk Based Ratios [Abstract]
Capital to Risk Weighted Assets	0.1458	0.1532
Tier One Risk Based Capital to Risk Weighted Assets	0.1333	0.1406
Common Equity Tier OneTo Risk Weighted Assets	13.33%	14.06%
Tier One Leverage Capital to Average Assets	0.0896	0.0981
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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