Tax Credit Investments - Income Statement Disclosures (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Components of Income Tax Expense:
Affordable housing tax credits and other tax benefits	$ 899	$ 1,393	$ 1,796	$ 2,627
Other tax credit investment credits and tax benefits	2,743	2,540	5,428	3,840
Total reduction in income tax expense	3,642	3,933	7,224	6,467
Non-Interest Expenses
Amortization of Tax Credit Investments:
Affordable housing tax credit investment losses	460	537	1,003	1,091
Affordable housing tax credit investment impairment losses	431	665	772	1,083
Other tax credit investment losses	351	679	524	1,223
Other tax credit investment impairment losses	1,730	1,535	3,417	3,247
Total amortization of tax credit investments recorded in non-interest expense	$ 2,972	$ 3,416	$ 5,716	$ 6,644