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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Per unit of ownership amount of cash distributions declared to unit-holder of a limited partnership (LP).

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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Subsequent Events (Details) - USD ($) $ / shares in Units, $ in Thousands							3 Months Ended		9 Months Ended
	Oct. 26, 2020	Oct. 19, 2020	Jul. 31, 2020	Jul. 20, 2020	Apr. 27, 2020	Apr. 16, 2020	Dec. 31, 2020	Sep. 30, 2019	Sep. 30, 2019	Oct. 07, 2020	Sep. 30, 2020	Dec. 31, 2019
Subsequent Event
Loss on early extinguishment of debt								$ 13,080	$ 13,080
Senior Notes 6.875 Percent Due 2029 [Member]
Subsequent Event
Stated interest rate (as a percent)										6.875%
Senior Notes 7.00 Percent Due 2023 [Member]
Subsequent Event
Aggregate principal amount											$ 300,000	$ 300,000
Stated interest rate (as a percent)											7.00%	7.00%
Series A Preferred Limited Partners
Subsequent Event
Quarterly cash distributions declared (in dollars per unit)				$ 0.609375		$ 0.609375
Common Limited Partners
Subsequent Event
Quarterly cash distributions declared (in dollars per unit)			$ 0.45875		$ 0.39375
Subsequent event \| Senior Notes 6.875 Percent Due 2029 [Member]
Subsequent Event
Aggregate principal amount										$ 350,000
Stated interest rate (as a percent)										6.875%
Subsequent event \| Senior Notes 7.00 Percent Due 2023 [Member]
Subsequent Event
Stated interest rate (as a percent)										7.00%
Loss on early extinguishment of debt							$ 7,200
Subsequent event \| Series A Preferred Limited Partners
Subsequent Event
Quarterly cash distributions declared (in dollars per unit)		$ 0.609375
Subsequent event \| Series A Preferred Limited Partners \| Annualized Basis [Member]
Subsequent Event
Quarterly cash distributions declared (in dollars per unit)		$ 2.4375
Subsequent event \| Common Limited Partners
Subsequent Event
Quarterly cash distributions declared (in dollars per unit)	$ 0.50000
Subsequent event \| Common Limited Partners \| Annualized Basis [Member]
Subsequent Event
Quarterly cash distributions declared (in dollars per unit)	$ 2.00