Partners' Capital, Mezzanine Capital and Distributions (Common Cash Distributions Paid) (Details) - Common Unitholders - USD ($) $ / shares in Units, $ in Thousands	May 15, 2020	Feb. 14, 2020	Nov. 14, 2019	Aug. 14, 2019	May 15, 2019
Partners Capital And Distributions [Line Items]
Date Paid		Feb. 14, 2020	Nov. 14, 2019	Aug. 14, 2019	May 15, 2019
Per Unit Amount (in dollars per unit)		$ 0.5500	$ 0.5500	$ 0.5500	$ 0.5500
Total Amount		$ 67,419	$ 67,419	$ 67,419	$ 67,419
Forecast | Subsequent Event
Partners Capital And Distributions [Line Items]
Date Paid	May 15, 2020
Per Unit Amount (in dollars per unit)	$ 0.1500
Total Amount	$ 18,387