Goodwill and Intangible Assets - Summary of Activity Related to Goodwill (Detail) $ in Thousands	3 Months Ended
	Mar. 31, 2017 USD ($)
Goodwill [Roll Forward]
Goodwill as of December 31, 2016, Net Carrying Amount	$ 231,787
Goodwill as of March 31, 2017, Net Carrying Amount	231,424
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Goodwill, Gross [Roll Forward]
Goodwill as of December 31, 2016, Gross Carrying Amount	271,443
Acquisition, Gross Carrying Amount	(363)
Goodwill as of March 31, 2017, Gross Carrying Amount	271,080
Accumulated Impairment Losses [Roll Forward]
Goodwill as of December 31, 2016, Accumulated Impairment Losses	(39,656)
Goodwill as of March 31, 2017, Accumulated Impairment Losses	(39,656)
Goodwill [Roll Forward]
Goodwill as of December 31, 2016, Net Carrying Amount	231,787
Acquisition, Net Carrying Amount	(363)
Goodwill as of March 31, 2017, Net Carrying Amount	$ 231,424