Derivative Instruments and Hedging Activities - Additional Information (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2021 USD ($) swap	Mar. 31, 2020 USD ($)	Dec. 31, 2020 USD ($)
Derivative [Line Items]
Aggregate fair value of net liability position	$ 11,600
Interest rate swaps
Derivative [Line Items]
Accumulated net after-tax losses related to effective cash flow hedges	3,100		$ 4,000
Reclassified to interest expense	2,700
Fair value hedge | Interest rate swaps | Noninterest Income
Derivative [Line Items]
Fee income related to derivative interest rate swaps executed with commercial loan customers	6,200	$ 14,200
Derivatives designated as hedging instruments:
Derivative [Line Items]
Notional amount	1,100,000		1,100,000
Derivatives not designated as hedging instruments:
Derivative [Line Items]
Notional amount	$ 9,822,126		9,211,043
Derivatives not designated as hedging instruments: | Interest rate swaps
Derivative [Line Items]
Number of instruments held | swap	25
Notional amount	$ 9,375,183		$ 8,889,557
Derivatives not designated as hedging instruments: | Interest rate swaps | Risk Participation Agreement
Derivative [Line Items]
Notional amount	$ 215,500
Derivatives not designated as hedging instruments: | Fair value hedge | Interest rate swaps
Derivative [Line Items]
Number of instruments held | swap	2
Notional amount	$ 10,400