Derivative Financial Instruments (Details 1) - Non-hedging - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Derivative [Line Items]
Estimated fair value, asset derivative	$ 143,050	$ 48,866
Estimated fair value, liability derivative	126,542	51,492
Offsetting derivative liabilities	0	(182)
Offsetting derivative assets	0	(182)
Net asset derivatives included in the consolidated balance sheets		48,684
Net liability derivatives included in the consolidated balance sheets		51,310
Interest rate swap futures
Derivative [Line Items]
Notional amount	255,000	0
Estimated fair value, asset derivative	2,460	0
Estimated fair value, liability derivative	3	0
Forward sale commitments
Derivative [Line Items]
Notional amount	153,000	0
Estimated fair value, asset derivative	1,067	0
Estimated fair value, liability derivative	0	0
Interest rate contract \| Loan purchase commitments
Derivative [Line Items]
Notional amount	1,215,599	214,012
Estimated fair value, asset derivative	20,580	1,965
Estimated fair value, liability derivative	3	4
Interest rate contract \| Loan purchase commitments
Derivative [Line Items]
Notional amount	1,311,974	2,654,653
Estimated fair value, asset derivative	0	0
Estimated fair value, liability derivative	7,593	4,587
Financial institution counterparties \| Commercial loan/lease \| Interest rate swap
Derivative [Line Items]
Notional amount	1,947,806	1,548,234
Estimated fair value, asset derivative	0	182
Estimated fair value, liability derivative	118,663	46,518
Financial institution counterparties \| Commercial loan/lease \| Interest rate cap
Derivative [Line Items]
Notional amount	657,109	639,163
Estimated fair value, asset derivative	42	32
Estimated fair value, liability derivative	0	0
Financial institution counterparties \| Commercial loan/lease \| Foreign currency forward contracts
Derivative [Line Items]
Notional amount	2,228	2,219
Estimated fair value, asset derivative	0	169
Estimated fair value, liability derivative	238	0
Customer counterparties \| Commercial loan/lease \| Interest rate swap
Derivative [Line Items]
Notional amount	1,947,806	1,548,234
Estimated fair value, asset derivative	118,663	46,518
Estimated fair value, liability derivative	0	182
Customer counterparties \| Commercial loan/lease \| Interest rate cap
Derivative [Line Items]
Notional amount	657,109	639,163
Estimated fair value, asset derivative	0	0
Estimated fair value, liability derivative	42	32
Customer counterparties \| Commercial loan/lease \| Foreign currency forward contracts
Derivative [Line Items]
Notional amount	2,228	2,219
Estimated fair value, asset derivative	238	0
Estimated fair value, liability derivative	$ 0	$ 169

Fair value of liability associated with financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset.

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