Securities (Summary of Investments) (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale debt securities, amortized cost	$ 1,190,434	$ 1,166,340
Available for sale debt securities, unrealized gains	129	270
Available for sale debt securities, unrealized losses	(168,105)	(172,682)
Available for sale debt securities, allowance for credit losses	0	0
Available for sale debt securities, fair value	1,022,458	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	250,952	231,203
Available for sale debt securities, unrealized gains	0	1
Available for sale debt securities, unrealized losses	(29,926)	(31,622)
Available for sale debt securities, allowance for credit losses	0	0
Available for sale debt securities, fair value	221,026	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	916,912	912,581
Available for sale debt securities, unrealized gains	129	269
Available for sale debt securities, unrealized losses	(135,857)	(138,748)
Available for sale debt securities, allowance for credit losses	0	0
Available for sale debt securities, fair value	781,184	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	9,394	9,387
Available for sale debt securities, unrealized gains	0	0
Available for sale debt securities, unrealized losses	(897)	(627)
Available for sale debt securities, allowance for credit losses	0	0
Available for sale debt securities, fair value	8,497	8,760
Corporate bonds [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale debt securities, amortized cost	13,176	13,169
Available for sale debt securities, unrealized gains	0	0
Available for sale debt securities, unrealized losses	(1,425)	(1,685)
Available for sale debt securities, allowance for credit losses	0	0
Available for sale debt securities, fair value	$ 11,751	$ 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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