Investment Securities (Narrative) (Details) - USD ($)	6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale	$ 1,170,706,000		$ 1,332,842,000
Debt Securities, Available-for-sale, Unrealized Loss Position	931,624,000		1,206,855,000
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	89,559,000		87,155,000
Securities Available-for-Sale, 12 months or longer, Fair value	866,385,000		1,150,640,000
Debt Securities, Available-for-sale, Allowance for Credit Loss	0		0
Other than Temporary Impairment Losses, Investments	0	$ 0
Debt Securities, Available-for-sale, Amortized Cost	$ 1,259,498,000		1,418,770,000
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%
Gain (Loss) on Sale of Investments	$ 398,000	0
Debt securities available for sale, securities sold	31,200,000	$ 0
U.S. Government Sponsored Entities Asset-Backed Securities [Member]
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale	570,839,000		635,475,000
Debt Securities, Available-for-sale, Unrealized Loss Position	569,653,000		634,261,000
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	69,975,000		68,193,000
Securities Available-for-Sale, 12 months or longer, Fair value	569,653,000		634,261,000
Debt Securities, Available-for-sale, Amortized Cost	640,810,000		703,645,000
USGovernmentSponsored asset backed securities and US Treasury obligations
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	70,000,000
Collateral Pledged [Member]
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Restricted	$ 731,900,000		$ 602,000,000.0