Acquisitions - Summary of Unaudited Pro Forma Financial Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Business Combinations [Abstract]
Net revenues	$ 387,528	$ 374,956	$ 727,744	$ 706,258
Net income applicable to common stock	$ 81,812	$ 57,743	$ 133,473	$ 93,923
Net income per common share — basic	$ 0.84	$ 0.60	$ 1.38	$ 0.98
Net income per common share — diluted	$ 0.84	$ 0.60	$ 1.37	$ 0.98

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=56956515&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 net Income or Loss for the 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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