Financing Arrangements - Schedule of Maturities of Principal Obligations Under Term Facility (Detail) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Less current portion	$ (3,650)	$ (3,650)
Total long-term debt	348,838	$ 349,858
Senior Secured Term Loan Facility [Member]
Debt Instrument [Line Items]
Remainder of 2016	1,825
2017	3,650
2018	3,650
2019	3,650
2020	3,650
2021 and thereafter	344,925
Total debt	361,350
Unamortized debt discount	(3,860)
Unamortized debt issuance costs	(5,002)
Total	352,488
Total	352,488
Less current portion	(3,650)
Total long-term debt	$ 348,838

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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