Debt Securities - Credit Quality Indicators for HTM Debt Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Debt securities, held-to-maturity	$ 1,199,164	$ 189,836
Moody's, Aaa Rating | Standard & Poor's, AAA Rating | Internal Investment Grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Debt securities, held-to-maturity	316,899	39,022
Moody's, Aa1, Aa2 or Aa3 Ratings | Standard & Poor's, AA+, AA or AA- Ratings | Internal Investment Grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Debt securities, held-to-maturity	841,616	123,664
Moody's, A1, A2 or A3 Ratings | Standard & Poor's, A+, A or A- Ratings | Internal Investment Grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Debt securities, held-to-maturity	39,078	27,150
Moody's, Not Rated | Standard & Poor's, Not Rated | Internal Investment Grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Debt securities, held-to-maturity	$ 1,571	$ 0