Schedule of Debt Obligations (Parenthetical) (Detail) - USD ($)		Aug. 02, 2017	Mar. 18, 2013	Jun. 30, 2017	Dec. 31, 2016	Sep. 30, 2016	Jul. 31, 2016	Jun. 30, 2016	May 23, 2011
Debt Instrument [Line Items]
Total debt	[1]			$ 961,957,000	$ 1,254,160,000
Convertible Notes | 1.50% Senior Subordinated Notes Due March 15, 2018
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage			1.50%	1.50%	1.50%			1.50%	2.50%
Debt instrument, par value of notes repurchased				$ 104,900,000		$ 104,900,000	$ 53,200,000	$ 51,700,000
Aggregate principal amount			$ 400,000,000	295,100,000					$ 300,000,000
Maturity date of credit agreement			Mar. 15, 2018
Total debt	[2]			$ 284,729,000	$ 277,518,000
Long Term Refinancing Arrangement | Senior Secured Term Loan Due 2022 | Subsequent Event | Deutsche Bank AG
Debt Instrument [Line Items]
Aggregate principal amount		$ 300,000,000
Terms of credit agreement		5 years
Maturity date of credit agreement		Aug. 02, 2022

[1] Carrying amounts include aggregate unamortized debt discount and debt issuance costs.

[2] During FY 2016, the Company repurchased a total of $104.9 million par value (of which $51.7 million and $53.2 million were purchased in June 2016 and July 2016, respectively) of the 1.50% Convertible Notes. See below for further details. On August 2, 2017, the Company entered into a long-term refinancing arrangement with Deutsche Bank AG for an aggregate principal amount of $300 million (refer to Note 20 for further details). In accordance with ASC 470, as the terms of the refinancing are readably determinable and the terms of the credit agreement is five years (scheduled to mature on August 2, 2022), the Company has classified the 1.50% Convertible Notes of $284.7 million as long-term debt on its June 30, 2017 condensed consolidated balance sheet.