Debt - Schedule of Interest Expense (Details) - Senior Notes - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
2027 Notes
Debt Instrument [Line Items]
Contractual interest coupon	$ 8.4	$ 8.4	$ 16.7	$ 16.7
Amortization of debt issuance costs	0.3	0.3	0.6	0.6
Total	$ 8.7	$ 8.7	$ 17.3	17.3
2021 Notes
Debt Instrument [Line Items]
Contractual interest coupon				0.8
Amortization of debt discount				0.5
Amortization of debt issuance costs				0.1
Total				$ 1.4

Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

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Amount of amortization expense attributable to debt issuance costs.

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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