Long-Term Debt (Details Textual) (USD $) |
3 Months Ended | 9 Months Ended | 1 Months Ended | 3 Months Ended | 9 Months Ended | 6 Months Ended | 9 Months Ended | 6 Months Ended | 9 Months Ended | 3 Months Ended | 1 Months Ended | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Sep. 30, 2011 |
Sep. 30, 2010 |
Sep. 30, 2011 |
Sep. 30, 2010 |
Dec. 31, 2010
Secured Debt [Member]
Prior Credit Facility [Member]
|
Sep. 30, 2011
Secured Debt [Member]
New Credit Facility [Member]
|
Dec. 31, 2010
Revolving credit facility [Member]
|
Dec. 31, 2010
Term Loan Portion [Member]
|
Mar. 31, 2011
New Credit Facility [Member]
|
Sep. 30, 2011
New Credit Facility [Member]
|
Jun. 30, 2011
New Credit Facility [Member]
|
Mar. 31, 2011
New Credit Facility [Member]
|
Sep. 30, 2011
New Credit Facility [Member]
|
Mar. 09, 2011
New Credit Facility [Member]
|
Sep. 30, 2011
New Credit Facility [Member]
Maximum [Member]
|
Sep. 30, 2011
New Credit Facility [Member]
Maximum [Member]
|
Sep. 30, 2011
New Credit Facility [Member]
Minimum [Member]
|
Sep. 30, 2011
New Credit Facility [Member]
Minimum [Member]
|
Mar. 31, 2011
Prior Credit Facility [Member]
|
Sep. 30, 2011
Prior Credit Facility [Member]
|
Dec. 31, 2010
Prior Credit Facility [Member]
|
Aug. 31, 2009
Maximum [Member]
|
Aug. 31, 2009
Minimum [Member]
|
|
| Long-Term Debt (Textual) [Abstract] | |||||||||||||||||||||||
| Senior secured revolving credit facility | $ 700,000,000 | ||||||||||||||||||||||
| New Credit Facility, maturity date | March 9, 2016 | ||||||||||||||||||||||
| Margin portion of interest rate in addition to LIBOR rate | 1.75% | ||||||||||||||||||||||
| Margin portion of interest rate in addition to base rate | 0.75% | ||||||||||||||||||||||
| Margin Portion of Interest Rate in Addition to LIBOR Rate after March 2011 | 2.50% | 1.50% | |||||||||||||||||||||
| Margin portion of interest rate in addition to base rate after March 2011 | 1.50% | 0.50% | |||||||||||||||||||||
| Line of Credit Facility, Unused Capacity, Commitment Fee Percentage | 0.50% | 0.25% | |||||||||||||||||||||
| Repayment of all amounts outstanding under the Prior Credit Facility by using borrowings under the New Credit Facility | 196,000,000 | ||||||||||||||||||||||
| Borrowings under Long-term Lines of Credit | 791,700,000 | 338,000,000 | 401,000,000 | 101,000,000 | 235,700,000 | 54,000,000 | |||||||||||||||||
| Repayments of Long-term Lines of Credit | 339,000,000 | 123,000,000 | 55,700,000 | 228,900,000 | |||||||||||||||||||
| Amounts outstanding | 31,000,000 | 143,900,000 | 220,000,000 | 220,000,000 | 0 | 174,900,000 | |||||||||||||||||
| Long-term Debt, Weighted Average Interest Rate | 1.75% | 1.72% | |||||||||||||||||||||
| Foreign currency borrowings outstanding | 0 | 0 | |||||||||||||||||||||
| Credit facility maturity | 5 years | ||||||||||||||||||||||
| Additional Long Term Debt (Textual) [Abstract] | |||||||||||||||||||||||
| Interest expense | 3,100,000 | 2,700,000 | 9,500,000 | 7,700,000 | |||||||||||||||||||
| Write-off of unamortized deferred financing costs resulting from the extinguishment of the prior senior secured facility | 914,000 | ||||||||||||||||||||||
| Debt issuance costs | $ 5,700,000 | $ 5,700,000 | |||||||||||||||||||||
| Line of Credit Facility, Interest Rate Description | The highest of Federal Funds Rate plus 0.50%, one-month LIBOR plus 1.00%, and the prime rate offered by Bank of America | LIBOR + 2.50% | LIBOR + 1.50% | ||||||||||||||||||||