Derivative Instruments - Derivatives Gross Amounts Recognized and Offset (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Derivative Assets
Gross amounts recognized	$ 178,591	$ 263,401
Gross amounts offset	(781)	(52)
Total derivative assets, net	177,810	263,349
Derivative Liabilities
Gross amounts recognized	24,310	21,132
Gross amounts offset	(627)	(1,876)
Net amount presented	23,683	19,256
Interest rate contracts
Derivative Assets
Gross amounts recognized	164,438	248,267
Gross amounts offset	0	0
Total derivative assets, net	164,438	248,267
Derivative Liabilities
Gross amounts recognized	21,945	14,681
Gross amounts offset	0	0
Net amount presented	21,945	14,681
Risk participation agreements
Derivative Assets
Gross amounts recognized	27	62
Gross amounts offset	0	0
Total derivative assets, net	27	62
Derivative Liabilities
Gross amounts recognized	63	125
Gross amounts offset	0	0
Net amount presented	63	125
Forward foreign exchange contracts
Derivative Assets
Gross amounts recognized	1,193	11
Gross amounts offset	(570)	(11)
Total derivative assets, net	623	0
Derivative Liabilities
Gross amounts recognized	1,505	2,386
Gross amounts offset	(130)	(1,769)
Net amount presented	1,375	617
Interest rate lock commitments
Derivative Assets
Gross amounts recognized	7,073	14,565
Gross amounts offset	(166)	(4)
Total derivative assets, net	6,907	14,561
Derivative Liabilities
Gross amounts recognized	166	4
Gross amounts offset	(166)	(4)
Net amount presented	0	0
Forward loan sales commitments
Derivative Assets
Gross amounts recognized	5,560	37
Gross amounts offset	(45)	(37)
Total derivative assets, net	5,515	0
Derivative Liabilities
Gross amounts recognized	45	3,411
Gross amounts offset	(45)	(37)
Net amount presented	0	3,374
Power Equity CDs
Derivative Assets
Gross amounts recognized	300	459
Gross amounts offset		0
Total derivative assets, net	300	459
Derivative Liabilities
Gross amounts recognized	300	459
Gross amounts offset		0
Net amount presented	300	459
Swap agreement
Derivative Liabilities
Gross amounts recognized	286	66
Gross amounts offset	(286)	(66)
Net amount presented	$ 0	$ 0

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