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

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Debt - Debt Repurchases (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
Debt - Debt Repurchases (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Extinguishment of Debt [Line Items]
Gain (loss) on extinguishment of debt	$ 594	$ 0	$ (5,147)	$ (574)
Senior Notes
Extinguishment of Debt [Line Items]
Interest rate	5.875%		5.875%
Senior Notes \| 6.00% Senior Notes due 2026
Extinguishment of Debt [Line Items]
Interest rate	6.00%		6.00%
Senior Notes \| 5.875% Senior Notes due 2024
Extinguishment of Debt [Line Items]
Interest rate	5.875%		5.875%
Senior Notes \| 5.125% Senior Notes, due 2023
Extinguishment of Debt [Line Items]
Interest rate	5.125%		5.125%
Senior Notes \| 5.875% Senior Notes due 2022
Extinguishment of Debt [Line Items]
Interest rate	5.875%		5.875%
Debt instrument, repurchased face amount	$ 34,000		$ 34,000
Redemption price, percentage of principal amount redeemed	97.48%
Repurchase amount	$ 33,100		$ 33,100
Gain (loss) on extinguishment of debt	$ 600