Fair Value of Financial Instruments - Additional Information (Detail) (Senior Subordinated Notes, USD $)	Jan. 24, 2013	Jan. 24, 2013 Early Conversion Payment	Jan. 24, 2013 2018 Notes	Jan. 24, 2013 2018 Notes Early Conversion Payment	Apr. 01, 2014 2019 Notes
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Effective percentage rate			6.00%		5.00%
Conversion of stock conversion price (in dollars per share)		$ 83.33		$ 83.33	$ 83.33
Principal amount of convertible notes, denominator	$ 1,000	$ 1,000	$ 1,000	$ 1,000	$ 1,000

Contractual interest rate for funds borrowed, under the debt agreement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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