Summary of Debt (Details) (USD $)
|
Sep. 30, 2014
|
Mar. 31, 2014
|
||||||||
---|---|---|---|---|---|---|---|---|---|---|
Debt Instruments [Abstract] | ||||||||||
Long-term debt, gross | $ 1,964,100,000 | $ 1,972,000,000 | ||||||||
Current portion of long-term debt | 29,500,000 | 29,000,000 | ||||||||
Long-term debt | 1,934,600,000 | 1,943,000,000 | ||||||||
Senior Secured Credit Facility | Credit Facility
|
||||||||||
Debt Instruments [Abstract] | ||||||||||
Long-term debt, gross | 1,913,600,000 | [1] | 1,921,900,000 | [1] | ||||||
Unamortized original issue discount | 18,300,000 | |||||||||
Senior Secured Credit Facility | Term Loan Facility
|
||||||||||
Debt Instruments [Abstract] | ||||||||||
Unamortized original issue discount | 16,900,000 | |||||||||
New Market Tax Credit | Other Debt
|
||||||||||
Debt Instruments [Abstract] | ||||||||||
Long-term debt, gross | 37,400,000 | [2] | 37,400,000 | [2] | ||||||
Aggregate loan receivable | 27,600,000 | |||||||||
8.875% Senior Notes due 2016 | Senior Notes
|
||||||||||
Debt Instruments [Abstract] | ||||||||||
Long-term debt, gross | 1,300,000 | 1,300,000 | ||||||||
Stated interest rate for senior notes | 8.875% | |||||||||
Other Subsidiary Debt | Other Debt
|
||||||||||
Debt Instruments [Abstract] | ||||||||||
Long-term debt, gross | $ 11,800,000 | [3] | $ 11,400,000 | [3] | ||||||
|