Derivative Financial Instruments (Details 1) - Non-hedging - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Derivative [Line Items]
Estimated fair value, asset derivative	$ 48,866	$ 29,574
Estimated fair value, liability derivative	51,492	49,143
Offsetting derivative liabilities	(182)	(7,768)
Offsetting derivative assets	(182)	(7,768)
Net asset derivatives included in the consolidated balance sheets	48,684	21,806
Net liability derivatives included in the consolidated balance sheets	51,310	41,375
Interest rate contract \| Loan purchase commitments
Derivative [Line Items]
Notional amount	214,012	167,984
Estimated fair value, asset derivative	1,965	1,442
Estimated fair value, liability derivative	4	6
Interest rate contract \| Loan purchase commitments
Derivative [Line Items]
Notional amount	2,654,653	1,928,527
Estimated fair value, asset derivative	0	0
Estimated fair value, liability derivative	4,587	21,005
Financial institution counterparties \| Commercial loan/lease \| Interest rate swap
Derivative [Line Items]
Notional amount	1,548,234	1,579,328
Estimated fair value, asset derivative	182	7,978
Estimated fair value, liability derivative	46,518	16,719
Financial institution counterparties \| Commercial loan/lease \| Interest rate cap
Derivative [Line Items]
Notional amount	639,163	606,950
Estimated fair value, asset derivative	32	1,109
Estimated fair value, liability derivative	0	4
Financial institution counterparties \| Commercial loan/lease \| Foreign currency forward contracts
Derivative [Line Items]
Notional amount	2,219	39,737
Estimated fair value, asset derivative	169	2,263
Estimated fair value, liability derivative	0	59
Customer counterparties \| Commercial loan/lease \| Interest rate swap
Derivative [Line Items]
Notional amount	1,548,234	1,579,328
Estimated fair value, asset derivative	46,518	16,719
Estimated fair value, liability derivative	182	7,978
Customer counterparties \| Commercial loan/lease \| Interest rate cap
Derivative [Line Items]
Notional amount	639,163	606,950
Estimated fair value, asset derivative	0	4
Estimated fair value, liability derivative	32	1,109
Customer counterparties \| Commercial loan/lease \| Foreign currency forward contracts
Derivative [Line Items]
Notional amount	2,219	39,737
Estimated fair value, asset derivative	0	59
Estimated fair value, liability derivative	$ 169	$ 2,263

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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