Regulatory Capital Requirements - Capital Conservation Buffer (Details)	Mar. 31, 2021	Dec. 31, 2020
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
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)	12.82	12.47
Effective total capital to risk-weighted assets (as a percent)	14.07	13.73
Capital conservation buffer
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Effective CET1 capital to risk-weighted assets (as a percent)	7
Effective Tier 1 capital to risk-weighted assets (as a percent)	8.5
Effective total capital to risk-weighted assets (as a percent)	10.5
Capital requirements above regulatory rate (as a percent)	2.50%