Net Income Per Limited Partner Unit - Schedule of Distributions (Details) - USD ($) $ / shares in Units, $ in Thousands				3 Months Ended		6 Months Ended
	Aug. 13, 2020	Aug. 14, 2019	May 15, 2019	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Distribution Made to Limited Partner [Line Items]
Partner distributions declared		$ 34,400	$ 33,000	$ 37,600	$ 34,400	$ 75,200	$ 67,400
Dividends declared per share (in dollars per share)		$ 0.3237	$ 0.3126
General Partner
Distribution Made to Limited Partner [Line Items]
Partner distributions declared		$ 400	$ 200	1,200	400	2,400	600
Limited Partners Common Units
Distribution Made to Limited Partner [Line Items]
Partner distributions declared		17,000	16,400	18,200	17,000	36,400	33,400
Limited Partners Subordinated Units
Distribution Made to Limited Partner [Line Items]
Partner distributions declared		$ 17,000	$ 16,400	$ 18,200	$ 17,000	$ 36,400	$ 33,400
Subsequent Event
Distribution Made to Limited Partner [Line Items]
Dividends declared per share (in dollars per share)	$ 0.3475