Derivative Instruments - Summary of Derivative Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Derivatives
Derivative Assets	$ 263,401	$ 106,642
Derivative Liabilities	21,132	14,312
Derivative asset netting	(52)	(540)
Derivative liability netting	(1,876)	(5,109)
Total derivative assets, net	263,349	106,102
Total derivative liabilities, net	19,256	9,203
Other assets
Derivatives
Derivative Assets	263,401	106,642
Derivative asset netting	(52)	(540)
Total derivative assets, net	263,349	106,102
Accrued expenses and other liabilities
Derivatives
Derivative Liabilities	21,132	14,312
Derivative liability netting	(1,876)	(5,109)
Total derivative liabilities, net	19,256	9,203
Derivatives designated as hedges | Other assets
Derivatives
Derivative Assets	59	0
Derivatives designated as hedges | Accrued expenses and other liabilities
Derivatives
Derivative Liabilities	1,521	3,419
Derivatives not designated as hedging instruments | Other assets
Derivatives
Derivative Assets	263,342	106,642
Derivatives not designated as hedging instruments | Accrued expenses and other liabilities
Derivatives
Derivative Liabilities	19,611	10,893
Interest rate contracts
Derivatives
Derivative Assets	248,267	102,893
Derivative Liabilities	14,681	6,040
Derivative asset netting	0	(492)
Derivative liability netting	0	(491)
Total derivative assets, net	248,267	102,401
Total derivative liabilities, net	14,681	5,549
Interest rate contracts | Derivatives designated as hedges
Derivatives
Notional Amount	150,000	150,000
Interest rate contracts | Derivatives designated as hedges | Other assets
Derivatives
Derivative Assets	59	0
Interest rate contracts | Derivatives designated as hedges | Accrued expenses and other liabilities
Derivatives
Derivative Liabilities	0	168
Interest rate contracts | Derivatives not designated as hedging instruments
Derivatives
Notional Amount	6,140,464	5,095,969
Interest rate contracts | Derivatives not designated as hedging instruments | Other assets
Derivatives
Derivative Assets	248,208	102,893
Interest rate contracts | Derivatives not designated as hedging instruments | Accrued expenses and other liabilities
Derivatives
Derivative Liabilities	14,681	5,872
Risk participation agreements
Derivatives
Derivative Assets	62	202
Derivative Liabilities	125	354
Derivative asset netting	0	0
Derivative liability netting	0	0
Total derivative assets, net	62	202
Total derivative liabilities, net	125	354
Risk participation agreements | Derivatives not designated as hedging instruments
Derivatives
Notional Amount	470,670	316,353
Risk participation agreements | Derivatives not designated as hedging instruments | Other assets
Derivatives
Derivative Assets	62	202
Risk participation agreements | Derivatives not designated as hedging instruments | Accrued expenses and other liabilities
Derivatives
Derivative Liabilities	125	354
Forward foreign exchange contracts
Derivatives
Derivative Assets	11
Derivative Liabilities	2,386	6,519
Derivative asset netting	(11)
Derivative liability netting	(1,769)	(4,214)
Total derivative assets, net	0
Total derivative liabilities, net	617	2,305
Forward foreign exchange contracts | Derivatives designated as hedges
Derivatives
Notional Amount	207,515	177,593
Forward foreign exchange contracts | Derivatives designated as hedges | Other assets
Derivatives
Derivative Assets	0	0
Forward foreign exchange contracts | Derivatives designated as hedges | Accrued expenses and other liabilities
Derivatives
Derivative Liabilities	1,521	3,251
Forward foreign exchange contracts | Derivatives not designated as hedging instruments
Derivatives
Notional Amount	90,647	262,656
Forward foreign exchange contracts | Derivatives not designated as hedging instruments | Other assets
Derivatives
Derivative Assets	11	0
Forward foreign exchange contracts | Derivatives not designated as hedging instruments | Accrued expenses and other liabilities
Derivatives
Derivative Liabilities	865	3,268
Interest rate lock commitments
Derivatives
Derivative Assets	14,565	2,772
Derivative Liabilities	4	20
Derivative asset netting	(4)	(7)
Derivative liability netting	(4)	(7)
Total derivative assets, net	14,561	2,765
Total derivative liabilities, net	0	13
Interest rate lock commitments | Derivatives not designated as hedging instruments
Derivatives
Notional Amount	447,278	158,111
Interest rate lock commitments | Derivatives not designated as hedging instruments | Other assets
Derivatives
Derivative Assets	14,565	2,772
Interest rate lock commitments | Derivatives not designated as hedging instruments | Accrued expenses and other liabilities
Derivatives
Derivative Liabilities	4	20
Forward loan sales commitments
Derivatives
Derivative Assets	37	41
Derivative Liabilities	3,411	289
Derivative asset netting	(37)	(41)
Derivative liability netting	(37)	(41)
Total derivative assets, net	0	0
Total derivative liabilities, net	3,374	248
Forward loan sales commitments | Derivatives not designated as hedging instruments
Derivatives
Notional Amount	535,244	174,013
Forward loan sales commitments | Derivatives not designated as hedging instruments | Other assets
Derivatives
Derivative Assets	37	41
Forward loan sales commitments | Derivatives not designated as hedging instruments | Accrued expenses and other liabilities
Derivatives
Derivative Liabilities	3,411	289
Power Equity CDs
Derivatives
Derivative Assets	459	734
Derivative Liabilities	459	734
Derivative asset netting	0	0
Derivative liability netting	0	0
Total derivative assets, net	459	734
Total derivative liabilities, net	459	734
Power Equity CDs | Derivatives not designated as hedging instruments
Derivatives
Notional Amount	16,752	29,009
Power Equity CDs | Derivatives not designated as hedging instruments | Other assets
Derivatives
Derivative Assets	459	734
Power Equity CDs | Derivatives not designated as hedging instruments | Accrued expenses and other liabilities
Derivatives
Derivative Liabilities	459	734
Swap agreement
Derivatives
Derivative Liabilities	66	356
Derivative liability netting	(66)	(356)
Total derivative liabilities, net	0	0
Swap agreement | Derivatives not designated as hedging instruments
Derivatives
Notional Amount	12,652	12,652
Swap agreement | Derivatives not designated as hedging instruments | Other assets
Derivatives
Derivative Assets	0	0
Swap agreement | Derivatives not designated as hedging instruments | Accrued expenses and other liabilities
Derivatives
Derivative Liabilities	$ 66	$ 356