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Long-Term Debt - Additional Information (Detail) | 3 Months Ended |  |  |
--- | --- | --- | --- | ---
Mar. 31, 2016 USD ($) | Mar. 31, 2015 USD ($) | Mar. 12, 2015 USD ($) | Oct. 03, 2012 USD ($)
Debt Instrument [Line Items] |  |  |  |
Leverage ratio | 1.8 |  |  |
Maximum [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Leverage ratio | 3.5 |  |  |
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 |  |  |
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 | $ 5,100,000 | $ 5,300,000 |  |
Letters of credit outstanding | $ 0 |  |  |
5.375% Notes [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Long-term debt, maturity date | Oct. 15, 2020 |  |  |
Aggregate principal amount |  |  |  | $ 250,000,000
Percentage of aggregate principal amount of outstanding | 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. |  |  |

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- Definition Amount of letters of credit issued and reducing availability under revolving credit facility. + References No definition available. + Details
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