Fair Value Measurement - Summary of Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Assets
Derivative asset	$ 682	$ 48,186
Liabilities
Derivative liability	7,293	13,848
Level 3
Liabilities
Derivative liability	(6,611)
Fair Value, Measurements, Recurring
Assets
Derivative asset	682	48,186
Liabilities
Derivative liability	7,293	13,848
Fair Value, Measurements, Recurring \| Level 1
Assets
Derivative asset	0	0
Liabilities
Derivative liability	0	0
Fair Value, Measurements, Recurring \| Level 2
Assets
Derivative asset	0	0
Liabilities
Derivative liability	0	0
Fair Value, Measurements, Recurring \| Level 3
Assets
Derivative asset	682	48,186
Liabilities
Derivative liability	$ 7,293	$ 13,848

Fair value, after the effects of master netting arrangements, of a 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. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13433-108611

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant