Regulatory Capital Requirements - Capital Conservation Buffer (Details)	Mar. 31, 2020	Dec. 31, 2019
Regulatory Capital Requirements
Effective CET1 capital to risk-weighted assets (as a percent)	4.50%	4.50%
Effective Tier 1 capital to risk-weighted assets (as a percent)	11.65%	11.88%
Effective total capital to risk-weighted assets (as a percent)	12.90%	12.81%

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Total Capital divided by risk weighted assets as defined in the regulations.

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Percentage of Common Equity Tier One Risk-based Capital to total risk-weighted assets, as defined by regulatory framework.

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Tier 1 capital divided by risk weighted assets as defined by regulations.

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