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Acquisition (Amortization Expense) (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Business Acquisition [Line Items]
2023		$ 8,368		$ 8,368
2024		8,114		8,114
2025		6,953		6,953
2026		3,017		3,017
2027		1,705		1,705
Thereafter		3,180		3,180
Finite-Lived Intangible Assets, Net		31,337		31,337
Amortization of Intangible Assets			$ 16,200	8,000	$ 13,000
Cowen Insurance
Business Acquisition [Line Items]
2023	$ 466		466
2024	466		466
2025	466		466
2026	466		466
2027	466		466
Thereafter	1,693		1,693
Finite-Lived Intangible Assets, Net	4,023		4,023
Amortization of Intangible Assets	400	$ 400
Portico
Business Acquisition [Line Items]
2023	3,376		3,376
2024	3,376		3,376
2025	3,235		3,235
2026	0		0
2027	0		0
Thereafter	0		0
Finite-Lived Intangible Assets, Net	9,987		9,987
Amortization of Intangible Assets			9,500	400
MHT Partners
Business Acquisition [Line Items]
2023	289		289
2024	209		209
2025	52		52
2026	0		0
2027	0		0
Thereafter	0		0
Finite-Lived Intangible Assets, Net	$ 550		550
Amortization of Intangible Assets			$ 300	$ 300	$ 100