Accumulated Other Comprehensive Income (Reclassification out of AOCI) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net Interest Income	$ 527,519	$ 500,111	$ 493,405
Income before income taxes	256,509	192,392	241,611
Income Tax Expense (Benefit)	(53,689)	(38,148)	(47,160)
Net income	202,820	154,244	194,451
Compensation and employee benefits	224,034	209,722	212,867
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)	315	285	2,132
Income before income taxes	3,333	285	2,132
Income Tax Expense (Benefit)	(775)	(66)	(496)
Net income	2,558	219	1,636
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	(598)	(414)	(319)
Income Tax Expense (Benefit)	139	96	74
Net income	(459)	(318)	(245)
Compensation and employee benefits	(598)	(414)	(319)
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	8,418	595
Income Tax Expense (Benefit)	(2,427)	(1,957)	(138)
Net income	8,014	6,461	457
Interest Rate Cash Flow Hedge Gain (Loss) Reclassified to Earnings, Net	10,441	8,418	595
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	$ 3,018	$ 0	$ 0