Acquisitions - Summary of Unaudited Pro Forma Information (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Business Combinations [Abstract]
Revenues	$ 1,641,009	$ 1,641,100	$ 1,208,148
Net income (loss)	$ 152,391	$ 31,382	$ (49,718)
Basic earnings (loss) per share	$ 0.76	$ 0.17	$ (0.30)
Basic weighted average number of common shares outstanding	200,252	182,196	166,628
Diluted earnings (loss) per share	$ 0.74	$ 0.16	$ (0.30)
Diluted weighted average number of common and common equivalent shares outstanding	205,793	190,896	166,628

The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)-(3)
-URI http://asc.fasb.org/extlink&oid=65885119&loc=d3e1392-128463

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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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