Supplemental Cash Flow Information - Changes in Operating Assets and Liabilities (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Supplemental Cash Flow Elements [Abstract]
Accounts receivable	$ 96,497	$ (6,488)	$ 136,660
Prepaid expenses and other	9,690	(10,607)	(1,618)
Accounts payable	(10,705)	(24,727)	(17,643)
Accrued liabilities and other	(57,149)	29,531	(56,768)
Total	$ 38,333	$ (12,291)	$ 60,631

The increase (decrease) during the reporting period in the aggregate amount of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

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- Definition

The increase (decrease) during the reporting period in amount due within one year (or one business cycle) from customers for the credit sale of goods and services.

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- Definition

The increase (decrease) during the reporting period in the aggregate amount of accrued expenses and other operating obligations not separately disclosed in the statement of cash flows.

+ References

No definition available.

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- Definition

The increase (decrease) during the reporting period of all assets and liabilities used in operating activities.

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- Definition

The increase (decrease) during the reporting period in the value of prepaid expenses and other assets not separately disclosed in the statement of cash flows, for example, deferred expenses, intangible assets, or income taxes.

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- References

No definition available.

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