Securities (Summary of Investments) (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale debt securities, amortized cost	$ 1,170,105	$ 1,166,340
Available for sale debt securities, unrealized gains	16	270
Available for sale debt securities, unrealized losses	(211,131)	(172,682)
Available for sale debt securities, allowance for credit losses	0	0
Available for sale debt securities, fair value	958,990	993,928
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	250,950	231,203
Available for sale debt securities, unrealized gains	0	1
Available for sale debt securities, unrealized losses	(34,388)	(31,622)
Available for sale debt securities, allowance for credit losses	0	0
Available for sale debt securities, fair value	216,562	199,582
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	896,579	912,581
Available for sale debt securities, unrealized gains	16	269
Available for sale debt securities, unrealized losses	(174,896)	(138,748)
Available for sale debt securities, allowance for credit losses	0	0
Available for sale debt securities, fair value	721,699	774,102
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	9,397	9,387
Available for sale debt securities, unrealized gains	0	0
Available for sale debt securities, unrealized losses	(632)	(627)
Available for sale debt securities, allowance for credit losses	0	0
Available for sale debt securities, fair value	8,765	8,760
Corporate bonds [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale debt securities, amortized cost	13,179	13,169
Available for sale debt securities, unrealized gains	0	0
Available for sale debt securities, unrealized losses	(1,215)	(1,685)
Available for sale debt securities, allowance for credit losses	0	0
Available for sale debt securities, fair value	$ 11,964	$ 11,484

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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