Investment Securities - Allowance for Credit Losses HTM (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Beginning balance	$ 1,618	$ 409	$ 2,915	$ 0
Provision for credit loss expense	(486)	(102)	(1,183)	(62)
Securities charged-off			(600)
Ending balance	1,132	307	1,132	307
State and political subdivisions
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Beginning balance	1,042	97	2,307	0
Provision for credit loss expense	(171)	(2)	(1,436)	37
Securities charged-off			0
Ending balance	871	95	871	95
Other securities
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Beginning balance	576	312	608	0
Provision for credit loss expense	(315)	(100)	253	(99)
Securities charged-off			(600)
Ending balance	$ 261	$ 212	$ 261	212
Cumulative Effect, Period of Adoption, Adjustment
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Beginning balance				369
Cumulative Effect, Period of Adoption, Adjustment | State and political subdivisions
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Beginning balance				58
Cumulative Effect, Period of Adoption, Adjustment | Other securities
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Beginning balance				$ 311