Securities (Summary of Investments) (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale debt securities, amortized cost	$ 1,137,057	$ 1,152,629
Available for sale debt securities, unrealized gains	158	261
Available for sale debt securities, unrealized losses	(167,155)	(152,510)
Available for sale debt securities, allowance for credit losses	0	0
Available for sale debt securities, fair value	970,060	1,000,380
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	250,450	250,450
Available for sale debt securities, unrealized gains	0	15
Available for sale debt securities, unrealized losses	(26,540)	(24,723)
Available for sale debt securities, allowance for credit losses	0	0
Available for sale debt securities, fair value	223,910	225,742
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	864,017	879,597
Available for sale debt securities, unrealized gains	158	246
Available for sale debt securities, unrealized losses	(139,405)	(125,887)
Available for sale debt securities, allowance for credit losses	0	0
Available for sale debt securities, fair value	724,770	753,956
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	9,404	9,400
Available for sale debt securities, unrealized gains	0	0
Available for sale debt securities, unrealized losses	(429)	(607)
Available for sale debt securities, allowance for credit losses	0	0
Available for sale debt securities, fair value	8,975	8,793
Corporate bonds [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale debt securities, amortized cost	13,186	13,182
Available for sale debt securities, unrealized gains	0	0
Available for sale debt securities, unrealized losses	(781)	(1,293)
Available for sale debt securities, allowance for credit losses	0	0
Available for sale debt securities, fair value	$ 12,405	$ 11,889

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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