Securities, Amortized Cost and Fair Value Securities Available for Sale Contractual Maturities (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Fiscal Year Maturity [Abstract]
Maturing within one year	$ 15,701
Maturing after one year but within five years	125,299
Maturing after five years but within ten years	230,998
Maturing after ten years	348,801
Amortized cost	720,799
U.S. agency residential mortgage-backed	337,140
U.S. agency commercial mortgage-backed	18,473
Private label mortgage-backed	81,154
Other asset backed	174,488
Amortized cost	1,332,054	$ 1,052,132
Available-for-sale Securities, Debt Maturities, Fair Value, Fiscal Year Maturity [Abstract]
Maturing within one year	15,849
Maturing after one year but within five years	128,338
Maturing after five years but within ten years	234,100
Maturing after ten years	355,191
Total available-for-sale securities fair value	733,478
U.S. agency residential mortgage-backed	337,860
U.S. agency commercial mortgage-backed	18,608
Private label mortgage-backed	82,311
Other asset backed	176,121
Total	$ 1,348,378	$ 1,072,159