Guarantor Financial Information - Consolidated Statements of Comprehensive Income (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Condensed Statement of Comprehensive Income [Line Items]
Net earnings (loss)	$ 278,798	$ 175,237	$ (139,039)
Amounts reclassified to net earnings during the year relating to cash flow hedging instruments	1,117	2,859	4,373
Comprehensive income (loss)	279,915	178,096	(134,666)
Eliminations [Member]
Condensed Statement of Comprehensive Income [Line Items]
Net earnings (loss)	(171,232)	(35,939)	(16,487)
Amounts reclassified to net earnings during the year relating to cash flow hedging instruments	0	0	0
Comprehensive income (loss)	(171,232)	(35,939)	(16,487)
Parent Issuer [Member]
Condensed Statement of Comprehensive Income [Line Items]
Net earnings (loss)	278,798	175,237	(139,039)
Amounts reclassified to net earnings during the year relating to cash flow hedging instruments	1,117	2,859	4,373
Comprehensive income (loss)	279,915	178,096	(134,666)
Guarantors [Member]
Condensed Statement of Comprehensive Income [Line Items]
Net earnings (loss)	98,077	38,676	19,341
Amounts reclassified to net earnings during the year relating to cash flow hedging instruments	0	0	0
Comprehensive income (loss)	98,077	38,676	19,341
Non-Guarantors [Member]
Condensed Statement of Comprehensive Income [Line Items]
Net earnings (loss)	73,155	(2,737)	(2,854)
Amounts reclassified to net earnings during the year relating to cash flow hedging instruments	0	0	0
Comprehensive income (loss)	$ 73,155	$ (2,737)	$ (2,854)

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 5
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