Acquisition - Summary of Unaudited Pro Forma Results of Operations (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012
Business Acquisition [Line Items]
Revenue	$ 2,654,400	$ 2,575,715
Net Income	$ 124,871	$ 126,352
Class L Common Stock [Member]
Business Acquisition [Line Items]
Income (loss) per share		$ 17.18
Income (loss) per share		$ 16.48
Common Class A [Member]
Business Acquisition [Line Items]
Income (loss) per share	$ 2.03	$ (4.11)
Income (loss) per share	$ 1.97	$ (4.11)

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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.

+ References

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=25497992&loc=d3e1392-128463

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- Definition

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.

+ References

+ Details

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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.

+ References

+ Details

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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.

+ References

+ Details

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