Securities (Summary of Investments) (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale debt securities, amortized cost	$ 1,165,816	$ 1,051,800
Available for sale debt securities, unrealized gains	125	6,862
Available for sale debt securities, unrealized losses	(183,368)	(15,803)
Available for sale debt securities, allowance for credit losses	0	0
Available for sale debt securities, fair value	982,573	1,042,859
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	231,204	200,953
Available for sale debt securities, unrealized gains	5	12
Available for sale debt securities, unrealized losses	(33,354)	(4,511)
Available for sale debt securities, allowance for credit losses	0	0
Available for sale debt securities, fair value	197,855	196,454
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	912,063	828,319
Available for sale debt securities, unrealized gains	120	6,850
Available for sale debt securities, unrealized losses	(147,919)	(10,207)
Available for sale debt securities, allowance for credit losses	0	0
Available for sale debt securities, fair value	764,264	824,962
Individual name issuer trust preferred debt securities
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale debt securities, amortized cost	9,384	9,373
Available for sale debt securities, unrealized gains	0	0
Available for sale debt securities, unrealized losses	(584)	(235)
Available for sale debt securities, allowance for credit losses	0	0
Available for sale debt securities, fair value	8,800	9,138
Corporate bonds [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale debt securities, amortized cost	13,165	13,155
Available for sale debt securities, unrealized gains	0	0
Available for sale debt securities, unrealized losses	(1,511)	(850)
Available for sale debt securities, allowance for credit losses	0	0
Available for sale debt securities, fair value	$ 11,654	$ 12,305

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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