Contractual interest rate for funds borrowed, under the debt agreement.

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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Reflects the difference between the fair value of payments made to legally extinguish a debt and its carrying value at that time. This item excludes the write-off of amounts previously capitalized as debt issuance costs.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Debt - Additional Information (Details) - USD ($)				1 Months Ended	3 Months Ended		9 Months Ended
Debt - Additional Information (Details) - USD ($)	Jun. 30, 2015	May 15, 2015	May 14, 2015	Mar. 31, 2016	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Debt Instrument [Line Items]
Dividends paid to common stockholders		$ 145,000,000					$ 0	$ 144,600,000
Gain (loss) on debt extinguishment					$ 0	$ 0	0	(22,200,000)
Write-off of deferred financing costs and debt discount							$ 0	8,400,000
Deferred financing costs capitalized								5,200,000
Loss on debt extinguishment [Member]
Debt Instrument [Line Items]
Gain (loss) on debt extinguishment								(18,600,000)
Senior Notes [Member] \| 7.75% senior unsecured notes due 2021 [Member]
Debt Instrument [Line Items]
Interest rate					7.75%		7.75%
Redemption of senior notes				$ 600,000
Senior Notes [Member] \| 8.375% senior secured notes due 2019 [Member]
Debt Instrument [Line Items]
Repayments of senior notes		$ 220,000,000
Interest rate		8.375%
Redemption price		106.281%
Premium paid on debt redemption								13,800,000
Senior Secured Notes and Line of Credit [Member] \| 8.375% senior secured notes due 2019 and senior secured term loan facility due March 2020 [Member] \| Loss on debt extinguishment [Member]
Debt Instrument [Line Items]
Write-off of deferred financing costs and debt discount								4,800,000
Secured Debt [Member] \| Line of Credit [Member] \| Senior secured term loan facility due September 2020 [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity			$ 730,000,000.0
Repayments of credit facility	$ 248,000,000
Secured Debt [Member] \| Line of Credit [Member] \| Senior secured term loan facility due September 2020 [Member] \| Loss on debt extinguishment [Member]
Debt Instrument [Line Items]
Write-off of deferred financing costs and debt discount								$ 3,600,000
Secured Debt [Member] \| Line of Credit [Member] \| Senior secured term loan facility due March 2020 [Member]
Debt Instrument [Line Items]
Repayments of credit facility			$ 339,100,000