Face (par) amount of debt instrument at time of issuance.

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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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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Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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

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Long-term Debt - 2026 Senior Notes Narrative (Details) - Senior Notes - Senior Notes due 2026 - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Jul. 31, 2018
Debt Instrument [Line Items]
Aggregate principal amount					$ 400,000,000.0
Stated interest rate					6.00%
Redemption price, percentage of principal amount of Notes redeemed			100.00%
Deferred financing costs incurred in connection with securing the 2026 Senior Notes	$ 11,800,000		$ 11,800,000
Interest expense	$ 6,300,000	$ 6,300,000	$ 19,000,000.0	$ 18,900,000