Regulatory Requirements - Narrative (Details)	Dec. 31, 2019	Dec. 31, 2018	Jan. 01, 2016
Regulatory Requirements [Abstract]
Common equity Tier 1 capital (to risk-weighted assets), for capital adequacy purposes ratio	4.50%	4.50%
Tier 1 capital (to risk-weighted assets), for capital adequacy purposes ratio	6.00%	6.00%
Total capital (to risk-weighted assets), for capital adequacy purposes ratio	8.00%	8.00%
Tier 1 capital (core) (to adjusted total assets), for capital adequacy purposes ratio	4.00%	4.00%
Tier 1 capital (core) (to adjusted total assets), for well capitalized under prompt corrective action provisions ratio	5.00%	5.00%
Common equity Tier 1 capital (to risk-weighted assets), for well capitalized under prompt corrective action provisions ratio	6.50%	6.50%
Tier 1 risk-based capital ratio	8.00%	8.00%
Total capital (to risk-weighted assets), for well capitalized under prompt corrective action provisions ratio	10.00%	10.00%
Tier 1 risk-based capital required for capital adequacy to risk-weighted assets, higher risk weight	2.50%
Capital conservation buffer			0.625%

Regulatory Capital Requirements under Banking Regulations [Abstract]

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Tier One Common Capital Required for Capital Adequacy to Risk Weighted Assets

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Tier One Common Capital Required to be Well Capitalized to Risk Weighted Assets

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Tier One Common Capital to Risk Weighted Assets, Capital Conservation Buffer

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Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets, Higher Risk Weight

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The minimum Total risk based capital ratio (total capital divided by risk weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The Total risk based capital ratio (total capital divided by risk weighted assets) required to be categorized as "well capitalized", in the regulatory framework for prompt corrective action.

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The minimum amount of Tier 1 Leverage Capital for capital adequacy purposes divided by average assets as defined in the regulations.

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The amount of Tier 1 Leverage Capital required to be categorized as well capitalized divided by average assets as defined in the regulatory framework for prompt corrective action.

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The Tier 1 capital ratio (Tier 1 capital divided by risk weighted assets) required to be categorized as "well capitalized" under the regulatory framework for prompt corrective action.

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