Derivative Instruments - Derivatives Gross Amounts Recognized and Offset (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Derivative Assets
Gross amounts recognized	$ 320,937	$ 106,642
Gross amounts offset	(4,834)	(540)
Total derivative assets, net	316,103	106,102
Derivative Liabilities
Gross amounts recognized	23,562	14,312
Gross amounts offset	(2,584)	(5,109)
Net amount presented	20,978	9,203
Interest rate contracts
Derivative Assets
Gross amounts recognized	299,207	102,893
Gross amounts offset	(2,252)	(492)
Total derivative assets, net	296,955	102,401
Derivative Liabilities
Gross amounts recognized	16,313	6,040
Gross amounts offset	(2,252)	(491)
Net amount presented	14,061	5,549
Risk participation agreements
Derivative Assets
Gross amounts recognized	88	202
Gross amounts offset	0	0
Total derivative assets, net	88	202
Derivative Liabilities
Gross amounts recognized	123	354
Gross amounts offset	0	0
Net amount presented	123	354
Interest rate lock commitments
Derivative Assets
Gross amounts recognized	18,525	2,772
Gross amounts offset	(1)	(7)
Total derivative assets, net	18,524	2,765
Derivative Liabilities
Gross amounts recognized	1	20
Gross amounts offset	(1)	(7)
Net amount presented	0	13
Forward loan sales commitments
Derivative Assets
Gross amounts recognized	63	41
Gross amounts offset	(63)	(41)
Total derivative assets, net	0	0
Derivative Liabilities
Gross amounts recognized	4,613	289
Gross amounts offset	(63)	(41)
Net amount presented	4,550	248
Power Equity CDs
Derivative Assets
Gross amounts recognized	535	734
Gross amounts offset	0	0
Total derivative assets, net	535	734
Derivative Liabilities
Gross amounts recognized	535	734
Gross amounts offset	0	0
Net amount presented	535	734
Forward foreign exchange contracts
Derivative Assets
Gross amounts recognized	2,519	0
Gross amounts offset	(2,518)	0
Total derivative assets, net	1	0
Derivative Liabilities
Gross amounts recognized	1,764	6,519
Gross amounts offset	(55)	(4,214)
Net amount presented	1,709	2,305
Swap agreement
Derivative Liabilities
Gross amounts recognized	213	356
Gross amounts offset	(213)	(356)
Net amount presented	$ 0	$ 0

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