Regulatory Capital Requirements (Details) $ in Thousands	Sep. 30, 2021 USD ($)	Dec. 31, 2020 USD ($)
Group [Member]
Capital [Abstract]
Actual - Total capital	$ 1,053,185	$ 1,096,766
Actual - Tier 1 capital	966,885	1,010,945
Actual -Common equity tier 1 capital	931,885	894,075
Actual - Tier 1 leverage capital	966,885	1,010,945
Minimum Capital - Total Capital	723,792	717,974
Minimum capital - Tier 1 capital	585,927	581,217
Minimum capital - Common equity tier 1 capital	482,528	478,649
Minimum capital - Tier 1 leverage capital	414,708	392,424
Minimum to be well capitalized - Total Capital	689,325	683,785
Minimum to be well capitalized - Tier 1 capital	551,460	547,028
Minimum to be well capitalized - Common equity tier 1 capital	448,062	444,460
Minimum to be well capitalized - Tier 1 leverage	$ 518,384	$ 490,530
Risk Based Ratios [Abstract]
Capital to Risk Weighted Assets	0.1528	0.1604
Tier One Risk Based Capital to Risk Weighted Assets	0.1403	0.1478
Common Equity Tier One To Risk Weighted Assets	0.1352	0.1308
Tier One Leverage Capital to Average Assets	0.0933	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	0.0700	0.0700
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 Asset	0.0650	0.0650
Tier One Leverage Capital Required to be Well Capitalized to Average Assets	0.0500	0.0500
Bank [Member]
Capital [Abstract]
Actual - Total capital	$ 1,007,817	$ 1,044,275
Actual - Tier 1 capital	921,975	786,731
Actual -Common equity tier 1 capital	921,975	956,845
Actual - Tier 1 leverage capital	921,975	956,845
Minimum Capital - Total Capital	719,898	714,480
Minimum capital - Tier 1 capital	582,774	578,388
Minimum capital - Common equity tier 1 capital	479,932	476,320
Minimum capital - Tier 1 leverage capital	411,478	390,304
Minimum to be well capitalized - Total Capital	685,617	680,457
Minimum to be well capitalized - Tier 1 capital	548,493	544,366
Minimum to be well capitalized - Common equity tier 1 capital	445,651	442,297
Minimum to be well capitalized - Tier 1 leverage	$ 514,348	$ 487,879
Risk Based Ratios [Abstract]
Capital to Risk Weighted Assets	0.1470	0.1532
Tier One Risk Based Capital to Risk Weighted Assets	0.1345	0.1406
Common Equity Tier One To Risk Weighted Assets	0.1345	0.1406
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	0.0700	0.0700
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 Asset	0.0650	0.0650
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 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 Tier 1 leverage capital as defined by regulatory framework.

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