Accumulated Other Comprehensive Income (Reclassification out of AOCI) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net Interest Income	$ 622,836	$ 527,519	$ 500,111
Income before income taxes	317,647	256,509	192,392
Income Tax Expense (Benefit)	(67,469)	(53,689)	(38,148)
Net income	250,178	202,820	154,244
Compensation and employee benefits	241,139	224,034	209,722
Reclassification out of Accumulated Other Comprehensive Income | Unrealized Gains and Losses on Available-for-Sale Debt Securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Debt Securities, Available-for-sale, Realized Gain (Loss)	(9)	315	285
Income before income taxes	7,805	3,333	285
Income Tax Expense (Benefit)	(1,738)	(775)	(66)
Net income	6,067	2,558	219
Reclassification out of Accumulated Other Comprehensive Income | Unrealized Gains and Losses on Pension Plan Liability
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income before income taxes	(524)	(598)	(414)
Income Tax Expense (Benefit)	122	139	96
Net income	(402)	(459)	(318)
Compensation and employee benefits	(524)	(598)	(414)
Reclassification out of Accumulated Other Comprehensive Income | Unrealized Gains and Losses from Hedging Instruments
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income before income taxes	10,441	10,441	8,418
Income Tax Expense (Benefit)	(2,178)	(2,427)	(1,957)
Net income	8,263	8,014	6,461
Interest Rate Cash Flow Hedge Gain (Loss) Reclassified to Earnings, Net	10,441	10,441	8,418
Reclassification out of Accumulated Other Comprehensive Income | Amortization of unrealized gains and losses related to available for sale securities transfer
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net Interest Income	$ 7,814	$ 3,018	$ 0