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Segment Reporting (Balance Sheet Information of Segment Assets) (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Segment Reporting Information [Line Items]
Goodwill	$ 58,100	$ 58,100
Intangible assets, net - Courier Capital	2,322
Other assets	272,267	301,711
Assets	6,288,052	6,117,085
Other Intangible Assets [Member]
Segment Reporting Information [Line Items]
Intangible assets, net - Courier Capital	2,322	2,637
Operating Segment [Member]
Segment Reporting Information [Line Items]
Goodwill	48,536	48,536
Assets	6,250,000	6,080,731
Reconciliation [Member]
Segment Reporting Information [Line Items]
Goodwill	9,585	9,585
Other assets	26,145	24,735
Elimination of intercompany receivables	0	(603)
Reconciliation [Member] | Other Intangible Assets [Member]
Segment Reporting Information [Line Items]
Intangible assets, net - Courier Capital	$ 2,322	$ 2,637

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