Debt and Financing Obligation - Schedule of Debt (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Total borrowings	$ 944.5	$ 800.5
Original issue discount	(4.1)	(4.3)
Debt issuance costs	(12.6)	(13.3)
Total debt and financing obligation	927.8	782.9
Less: current portion of financing obligation	3.0	2.9
Long-term debt and financing obligation	924.8	780.0
7.500 percent senior notes, due 2025 (2025 Senior Notes) \| Senior notes
Debt Instrument [Line Items]
Total borrowings	$ 638.0	650.0
Interest rate on senior notes (as a percent)	7.50%
Revolving credit facility, due 2024 (Revolving Facility) \| Line of Credit \| Revolving Credit Facility
Debt Instrument [Line Items]
Total borrowings	$ 300.0	143.3
5.82 percent financing obligation, due 2021 (Financing Obligation) \| Financing Obligation
Debt Instrument [Line Items]
Total borrowings	$ 6.5	$ 7.2
Interest rate on senior notes (as a percent)	5.82%

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount, after accumulated amortization, of debt discount.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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