Derivative Financial Instruments (Details 1) - Non-hedging - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Derivative [Line Items]
Estimated fair value, asset derivative	$ 125,913	$ 48,866
Estimated fair value, liability derivative	126,459	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 contract \| Loan purchase commitments
Derivative [Line Items]
Notional amount	636,277	214,012
Estimated fair value, asset derivative	11,690	1,965
Estimated fair value, liability derivative	5	4
Interest rate contract \| Loan purchase commitments
Derivative [Line Items]
Notional amount	820,553	2,654,653
Estimated fair value, asset derivative	0	0
Estimated fair value, liability derivative	12,231	4,587
Financial institution counterparties \| Commercial loan/lease \| Interest rate swap
Derivative [Line Items]
Notional amount	1,929,103	1,548,234
Estimated fair value, asset derivative	0	182
Estimated fair value, liability derivative	113,742	46,518
Financial institution counterparties \| Commercial loan/lease \| Interest rate cap
Derivative [Line Items]
Notional amount	665,317	639,163
Estimated fair value, asset derivative	64	32
Estimated fair value, liability derivative	0	0
Financial institution counterparties \| Commercial loan/lease \| Foreign currency forward contracts
Derivative [Line Items]
Notional amount	2,971	2,219
Estimated fair value, asset derivative	417	169
Estimated fair value, liability derivative	0	0
Customer counterparties \| Commercial loan/lease \| Interest rate swap
Derivative [Line Items]
Notional amount	1,929,103	1,548,234
Estimated fair value, asset derivative	113,742	46,518
Estimated fair value, liability derivative	0	182
Customer counterparties \| Commercial loan/lease \| Interest rate cap
Derivative [Line Items]
Notional amount	665,317	639,163
Estimated fair value, asset derivative	0	0
Estimated fair value, liability derivative	64	32
Customer counterparties \| Commercial loan/lease \| Foreign currency forward contracts
Derivative [Line Items]
Notional amount	2,971	2,219
Estimated fair value, asset derivative	0	0
Estimated fair value, liability derivative	$ 417	$ 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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