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Long-Term Debt - Additional Information (Detail) |  |  | 9 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | ---
Sep. 07, 2018 | Feb. 01, 2017 | Sep. 30, 2018 USD ($) | Dec. 31, 2017 USD ($) | Mar. 12, 2015 USD ($) | Oct. 03, 2012 USD ($)
Debt Instrument [Line Items] |  |  |  |  |  |
Debt instrument covenant compliance leverage ratio, threshold |  |  | 4.0 |  |  |
Debt instrument covenant compliance leverage ratio, actual |  |  | 2.9 |  |  |
5.375% Notes [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Long-term debt, maturity date |  |  | Oct. 15, 2020 |  |  |
Aggregate principal amount |  |  |  |  |  | $ 250,000,000
Interest rate on debt |  |  | 5.375% |  |  | 5.375%
Frequency of interest payable |  |  | Semiannually |  |  |
Debt instrument redemption |  |  | The 5.375% Notes are redeemable, in whole or in part, at any time on or after October 15, 2016 at the redemption prices specified in the applicable Indenture. |  |  |
Revolving Credit Facility [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Line of credit facility, maximum borrowing capacity |  |  |  |  | $ 400,000,000 |
Long-term debt, maturity date |  |  | Mar. 12, 2020 |  |  |
Debt instrument covenant compliance leverage ratio, threshold | 4.0 | 4.0 |  |  |  |
Federal fund rate spread |  |  | 1.00% |  |  |
Revolving Credit Facility [Member] | Minimum [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Federal fund rate spread |  |  | 0.125% |  |  |
Revolving Credit Facility [Member] | Maximum [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Federal fund rate spread |  |  | 1.00% |  |  |
Revolving Credit Facility [Member] | Federal Funds Rate [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Federal fund rate spread |  |  | 0.50% |  |  |
Revolving Credit Facility [Member] | Daily Euro Rate [Member] | Minimum [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Federal fund rate spread |  |  | 1.125% |  |  |
Revolving Credit Facility [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 |  |  | $ 5,200,000 | $ 5,200,000 |  |
Letters of credit outstanding |  |  | $ 0 |  |  |

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