Derivative Instruments - Derivatives Gross Amounts Recognized and Offset (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Derivative Assets
Gross amounts recognized	$ 301,802	$ 106,642
Gross amounts offset	(2,861)	(540)
Total derivative assets, net	298,941	106,102
Derivative Liabilities
Gross amounts recognized	15,840	14,312
Gross amounts offset	498	(5,109)
Net amount presented	16,338	9,203
Interest rate contracts
Derivative Assets
Gross amounts recognized	279,710	102,893
Gross amounts offset	0	(492)
Total derivative assets, net	279,710	102,401
Derivative Liabilities
Gross amounts recognized	14,085	6,040
Gross amounts offset	0	(491)
Net amount presented	14,085	5,549
Risk participation agreements
Derivative Assets
Gross amounts recognized	163	202
Gross amounts offset	0	0
Total derivative assets, net	163	202
Derivative Liabilities
Gross amounts recognized	171	354
Gross amounts offset	0	0
Net amount presented	171	354
Forward foreign exchange contracts
Derivative Assets
Gross amounts recognized	2,774	0
Gross amounts offset	(2,740)	0
Total derivative assets, net	34	0
Derivative Liabilities
Gross amounts recognized	210	6,519
Gross amounts offset	760	(4,214)
Net amount presented	970	2,305
Interest rate lock commitments
Derivative Assets
Gross amounts recognized	18,596	2,772
Gross amounts offset	(4)	(7)
Total derivative assets, net	18,592	2,765
Derivative Liabilities
Gross amounts recognized	4	20
Gross amounts offset	(4)	(7)
Net amount presented	0	13
Forward loan sales commitments
Derivative Assets
Gross amounts recognized	117	41
Gross amounts offset	(117)	(41)
Total derivative assets, net	0	0
Derivative Liabilities
Gross amounts recognized	786	289
Gross amounts offset	(117)	(41)
Net amount presented	669	248
Power Equity CDs
Derivative Assets
Gross amounts recognized	442	734
Gross amounts offset	0	0
Total derivative assets, net	442	734
Derivative Liabilities
Gross amounts recognized	443	734
Gross amounts offset	0	0
Net amount presented	443	734
Swap agreement
Derivative Liabilities
Gross amounts recognized	141	356
Gross amounts offset	(141)	(356)
Net amount presented	$ 0	$ 0

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