Fair Value Measurements - Narrative (Details) - Senior Notes due 2024 - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020	May 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net unamortized debt issuance costs	$ 0.0	$ 2.4
Stated interest rate	5.125%		5.875%

Amount, after accumulated amortization, of debt discount (premium).

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant