Financial Instruments - Offsetting Assets and Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Total asset derivatives
Gross amounts presented in the consolidated balance sheet	$ 0	$ 5,330
Gross amounts not offset in the consolidated balance sheet subject to netting agreements	0	(216)
Net amount	0	5,114
Total liability derivatives
Gross amounts presented in the consolidated balance sheet	28,657	4,597
Gross amounts not offset in the consolidated balance sheet subject to netting agreements	0	(216)
Net amount	$ 28,657	$ 4,381

Fair value, after effects of master netting arrangements, deduction of assets not subject to a master netting arrangement and elected not to be offset, of 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, offset against an obligation to return collateral.

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- Definition

Fair value of 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, elected not to be offset, deducted from derivative assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Topic 210
-SubTopic 20
-Section 55
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Fair value, after the effects of master netting arrangements, of a 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. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

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+ References

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+ References

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