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Long-Term Debt - Additional Information (Detail) |  | 9 Months Ended |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Sep. 30, 2015 USD ($) | Sep. 30, 2015 USD ($) Installment DebtAgreements | Mar. 12, 2015 USD ($) | Dec. 31, 2014 USD ($) | Sep. 04, 2014 EUR (€) | Sep. 04, 2014 USD ($) | Apr. 11, 2013 EUR (€) | Apr. 11, 2013 USD ($) | Oct. 03, 2012 USD ($)
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Margin over Euro-rate | 1.00% | 1.00% |  |  |  |  |  |  |
Leverage ratio | 220.00% |  |  |  |  |  |  |  |
Other Assets [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Aggregated unamortized deferred debt issuance costs | $ 5,600,000 | $ 5,600,000 |  |  |  |  |  |  |
Maximum [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Leverage ratio |  | 350.00% |  |  |  |  |  |  |
Revolving Credit Facility [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Line of credit facility, maximum borrowing capacity |  |  | $ 400,000,000 |  |  |  |  |  |
Debt instrument maturity date |  | Mar. 12, 2020 |  |  |  |  |  |  |
Revolving Credit Facility [Member] | Federal Funds Rate [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Federal fund rate spread |  | 0.50% |  |  |  |  |  |  |
Revolving Credit Facility, Due Nov. 2016 [Member] | Minimum [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Federal fund rate spread |  | 0.125% |  |  |  |  |  |  |
Revolving Credit Facility, Due Nov. 2016 [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Federal fund rate spread |  | 1.00% |  |  |  |  |  |  |
Revolving Credit Facility, Due Nov. 2016 [Member] | Daily Euro Rate [Member] | Minimum [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Federal fund rate spread |  | 1.125% |  |  |  |  |  |  |
Revolving Credit Facility, Due Nov. 2016 [Member] | Daily Euro Rate [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Federal fund rate spread |  | 2.00% |  |  |  |  |  |  |
Letters of Credit [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Letters of credit issued | 5,300,000 | $ 5,300,000 |  | $ 5,300,000 |  |  |  |  |
Letters of credit outstanding | $ 0 | $ 0 |  |  |  |  |  |  |
5.375% Notes [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Debt instrument maturity date |  | Oct. 15, 2020 |  |  |  |  |  |  |
Aggregate principal amount |  |  |  |  |  |  |  |  | $ 250,000,000
Percentage of aggregate principal amount of outstanding | 5.375% | 5.375% |  |  |  |  |  |  | 5.375%
Frequency of interest payable |  | Semiannually |  |  |  |  |  |  |
Debt instrument redemption |  | The 5.375% Notes are redeemable, in whole or in part, at anytime on or after October 15, 2016 at the redemption prices specified in the applicable Indenture. Prior to October 15, 2016, we may redeem some or all of the Notes at a "make-whole" premium as specified in the Indenture. |  |  |  |  |  |  |
IKB Loan [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Aggregate principal amount |  |  |  |  |  |  | € 42,700,000 | $ 57,600,000 |
Percentage of aggregate principal amount of outstanding | 2.05% | 2.05% |  |  |  |  |  |  |
Number of separate loan agreement | DebtAgreements |  | 2 |  |  |  |  |  |  |
Number of installments | Installment |  | 32 |  |  |  |  |  |  |
Installments beginning date |  | Jun. 30, 2015 |  |  |  |  |  |  |
Installments ending date |  | Mar. 31, 2023 |  |  |  |  |  |  |
2014 IKB Loan [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Aggregate principal amount |  |  |  |  | € 10,000,000 | $ 12,600,000 |  |  |
Percentage of aggregate principal amount of outstanding | 2.40% | 2.40% |  |  |  |  |  |  |
Frequency of interest payable |  | Quarterly |  |  |  |  |  |  |
Number of installments | Installment |  | 27 |  |  |  |  |  |  |
Installments beginning date |  | Sep. 30, 2015 |  |  |  |  |  |  |
Installments ending date |  | Jun. 30, 2022 |  |  |  |  |  |  |

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