Goodwill and Intangible Assets - Summary of Activity Related to Goodwill (Detail) $ in Thousands	9 Months Ended
Sep. 30, 2016 USD ($)
Goodwill, Gross [Roll Forward]
Goodwill as of December 31, 2015, Gross Carrying Amount	$ 260,115
Acquisition, Gross Carrying Amount	2,235
Goodwill as of September 30, 2016, Gross Carrying Amount	262,350
Accumulated Impairment Losses [Roll Forward]
Goodwill as of December 31, 2015, Accumulated Impairment Losses	(39,656)
Goodwill as of September 30, 2016, Accumulated Impairment Losses	(39,656)
Goodwill [Roll Forward]
Goodwill as of December 31, 2015, Net Carrying Amount	220,459
Acquisition, Net Carrying Amount	2,235
Goodwill as of September 30, 2016, Net Carrying Amount	$ 222,694

Accumulated Impairment Losses [Roll Forward]

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- Definition

Goodwill, Gross [Roll Forward]

+ References

No definition available.

+ Details

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=64834752&loc=SL49117168-202975

+ Details

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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

+ Details

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- Definition

Amount before accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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- Definition

Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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