Securities (Summary of Investments) (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale debt securities, amortized cost	$ 1,051,800	$ 881,570
Available for sale debt securities, unrealized gains	6,862	15,570
Available for sale debt securities, unrealized losses	(15,803)	(2,569)
Allowance for credit losses on securities	0	0
Available for sale debt securities, fair value	1,042,859	894,571
Obligations of U.S. government-sponsored enterprises [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale debt securities, amortized cost	200,953	131,186
Available for sale debt securities, unrealized gains	12	628
Available for sale debt securities, unrealized losses	(4,511)	(145)
Allowance for credit losses on securities	0	0
Available for sale debt securities, fair value	196,454	131,669
Mortgage-backed securities issued by U.S. government-sponsored agencies and U.S. government-sponsored enterprises [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale debt securities, amortized cost	828,319	725,890
Available for sale debt securities, unrealized gains	6,850	14,942
Available for sale debt securities, unrealized losses	(10,207)	(527)
Allowance for credit losses on securities	0	0
Available for sale debt securities, fair value	824,962	740,305
Individual name issuer trust preferred debt securities [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale debt securities, amortized cost	9,373	13,341
Available for sale debt securities, unrealized gains	0	0
Available for sale debt securities, unrealized losses	(235)	(672)
Allowance for credit losses on securities	0	0
Available for sale debt securities, fair value	9,138	12,669
Corporate bonds [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale debt securities, amortized cost	13,155	11,153
Available for sale debt securities, unrealized gains	0	0
Available for sale debt securities, unrealized losses	(850)	(1,225)
Allowance for credit losses on securities	0	0
Available for sale debt securities, fair value	$ 12,305	$ 9,928

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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