Derivatives (Offsetting of Derivatives) (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Derivative assets
Gross Amounts Recognized	$ 764,430	$ 330,316
Less: Master netting agreements	(110,569)	(121,561)
Less: Cash collateral received/pledged	(11,649)	(3,758)
Derivative asset, after netting	642,212	204,997
Less: Security Collateral Received	(13,447)	0
Net derivative assets	628,765	204,997
Derivative assets subject to master netting arrangements, gross amounts recognized	754,700	328,700
Contracts not subject to master netting arrangements, gross amounts recognized	9,700	1,600
Derivative, cash collateral received, including amount offset by fair value assets, and excess cash amount	18,100	3,800
Amount used to offset against derivative assets	11,649	3,758
Derivative liabilities
Gross Amounts Recognized	560,169	256,528
Less: Master netting agreements	(110,569)	(121,561)
Less: Cash collateral received/pledged	(94,435)	(38,238)
Derivative liability, after netting	355,165	96,729
Less: Security Collateral Pledged	(279,528)	(79,619)
Net derivative liabilities	75,637	17,110
Derivative liability subject to master netting arrangements, gross amounts recognized	560,000	256,528
Contracts not subject to master netting arrangements, gross amounts recognized	211	20
Derivative, cash collateral posted against derivative liabilities, including amount offset the derivative fair value liabilities, and excess cash amount	98,900	43,000
Amount used to offset against derivative liabilities	$ 94,435	$ 38,238

Derivative Assets Subject To Master Netting Arrangements, Gross Amounts Recognized

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Derivative, Cash Collateral Posted Against Derivative Liabilities, Including Amount Offset the Derivative Fair Value Liabilities, and Excess Cash Amount

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Fair value of asset associated with financial liability or 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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