Derivative Instruments - Derivatives Gross Amounts Recognized and Offset (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Derivative Assets
Gross amounts recognized	$ 263,401	$ 106,642
Gross amounts offset	(52)	(540)
Net amount presented	263,349	106,102
Derivative Liabilities
Gross amounts recognized	21,132	14,312
Gross amounts offset	(1,876)	(5,109)
Net amount presented	19,256	9,203
Interest rate contracts
Derivative Assets
Gross amounts recognized	248,267	102,893
Gross amounts offset	0	(492)
Net amount presented	248,267	102,401
Derivative Liabilities
Gross amounts recognized	14,681	6,040
Gross amounts offset	0	(491)
Net amount presented	14,681	5,549
Risk participation agreements
Derivative Assets
Gross amounts recognized	62	202
Gross amounts offset	0	0
Net amount presented	62	202
Derivative Liabilities
Gross amounts recognized	125	354
Gross amounts offset	0	0
Net amount presented	125	354
Forward foreign exchange contracts
Derivative Assets
Gross amounts recognized	11
Gross amounts offset	(11)
Net amount presented	0
Derivative Liabilities
Gross amounts recognized	2,386	6,519
Gross amounts offset	(1,769)	(4,214)
Net amount presented	617	2,305
Interest rate lock commitments
Derivative Assets
Gross amounts recognized	14,565	2,772
Gross amounts offset	(4)	(7)
Net amount presented	14,561	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	37	41
Gross amounts offset	(37)	(41)
Net amount presented	0	0
Derivative Liabilities
Gross amounts recognized	3,411	289
Gross amounts offset	(37)	(41)
Net amount presented	3,374	248
Power Equity CDs
Derivative Assets
Gross amounts recognized	459	734
Gross amounts offset	0	0
Net amount presented	459	734
Derivative Liabilities
Gross amounts recognized	459	734
Gross amounts offset	0	0
Net amount presented	459	734
Swap agreement
Derivative Liabilities
Gross amounts recognized	66	356
Gross amounts offset	(66)	(356)
Net amount presented	$ 0	$ 0

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