Securities (Summary of Investments) (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale debt securities, amortized cost	$ 1,082,203	$ 1,051,800
Available for sale debt securities, unrealized gains	920	6,862
Available for sale debt securities, unrealized losses	74,939	15,803
Available for sale debt securities, allowance for credit losses	0	0
Available for sale debt securities, fair value	1,008,184	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	201,206	200,953
Available for sale debt securities, unrealized gains	0	12
Available for sale debt securities, unrealized losses	15,774	4,511
Available for sale debt securities, allowance for credit losses	0	0
Available for sale debt securities, fair value	185,432	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	858,461	828,319
Available for sale debt securities, unrealized gains	920	6,850
Available for sale debt securities, unrealized losses	57,811	10,207
Available for sale debt securities, allowance for credit losses	0	0
Available for sale debt securities, fair value	801,570	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	9,377	9,373
Available for sale debt securities, unrealized gains	0	0
Available for sale debt securities, unrealized losses	358	235
Available for sale debt securities, allowance for credit losses	0	0
Available for sale debt securities, fair value	9,019	9,138
Corporate bonds [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale debt securities, amortized cost	13,159	13,155
Available for sale debt securities, unrealized gains	0	0
Available for sale debt securities, unrealized losses	996	850
Available for sale debt securities, allowance for credit losses	0	0
Available for sale debt securities, fair value	$ 12,163	$ 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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