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Debt - Additional Information (Detail) (USD $)
In Millions, unless otherwise specified |
12 Months Ended | 12 Months Ended | 9 Months Ended | 12 Months Ended | 9 Months Ended | 12 Months Ended | 9 Months Ended | 12 Months Ended | |||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
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Dec. 31, 2011
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Jun. 30, 2013
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Dec. 31, 2012
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Dec. 31, 2011
Federal Funds Rate
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Sep. 30, 2012
LIBOR
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Dec. 31, 2011
LIBOR
|
Sep. 30, 2012
LIBOR
Minimum
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Dec. 31, 2011
LIBOR
Minimum
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Sep. 30, 2012
LIBOR
Maximum
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Dec. 31, 2011
LIBOR
Maximum
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Dec. 31, 2011
Wells fargo's prime rate
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Dec. 31, 2011
Wells fargo's prime rate
Minimum
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Dec. 31, 2011
Wells fargo's prime rate
Maximum
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Dec. 31, 2011
Standby Letters of Credit
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Dec. 31, 2011
Revolving Credit Facility
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| Line of Credit Facility [Line Items] | |||||||||||||||
| Sub limit for issuance of letters of credit | $ 10.0 | ||||||||||||||
| Revolving line of credit facility, available borrowing capacity | 150.0 | 150.0 | |||||||||||||
| Principal together with accrued and unpaid interest due and payable, date | Dec. 30, 2015 | ||||||||||||||
| Interest rate descriptions | Revolving loans accrue interest at a per annum rate equal to, at the Company's option, either LIBOR or Wells Fargo's prime rate (or, if greater, the federal funds rate plus 0.50% or three month LIBOR plus 1.00%), in each case plus a margin ranging from 2.50% to 3.00%, in the case of LIBOR loans, and 0.00% to 0.25% in the case of prime rate loans, based upon the Company's senior leverage ratio. | The federal funds rate plus 0.50% | The terms of the amendment, the LIBOR rate margin ranges from 2.00% to 2.50%, based on our senior leverage ratio | 2.50% to 3.00% plus LIBOR | 0.00% to 0.25% plus Wells Fargo's prime rate | ||||||||||
| Basis spread on interest rate | 0.50% | 1.00% | 2.00% | 2.50% | 2.50% | 3.00% | 0.00% | 0.25% | |||||||
| Revolving line of credit, outstanding amount | 0 | 10.0 | |||||||||||||
| Unamortized debt issuance costs | 0.5 | 0.8 | |||||||||||||
| Issuance of letters of credit outstanding, amount | $ 10.0 | ||||||||||||||