Long-Term Debt - Components of Long-Term Debt (Parenthetical) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015
Debt Instrument [Line Items]
Long-term debt, face amount	$ 25.0
Senior Secured Notes, 7.25% [Member]
Debt Instrument [Line Items]
Long-term debt, face amount	53.5
Senior Secured Notes, 6.47% [Member]
Debt Instrument [Line Items]
Long-term debt, face amount	110.0
Senior Secured Notes, 8.50% [Member]
Debt Instrument [Line Items]
Long-term debt, face amount	25.0
Senior Secured Notes, 5.04% [Member]
Debt Instrument [Line Items]
Long-term debt, face amount	60.0
Senior Secured Credit Facilities, 2.42% [Member]
Debt Instrument [Line Items]
Long-term debt, face amount	$ 407.0