Preferred Units (Details) - USD ($) $ / shares in Units, $ in Thousands		6 Months Ended
	Nov. 28, 2017	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Preferred Units
Class of Stock [Line Items]
Partners' equity, preferred units, outstanding (in shares)		0
Preferred units distribution rate		10.00%
Adjusted conversion price (in us dollars per share)		$ 14.2683
Number of preferred units redeemed		2,115
Preferred stock, redemption amount		$ 2,100
Number of preferred units converted (in shares)		24,248
Conversion of preferred units to common units		$ 24,200
Common Units
Class of Stock [Line Items]
Adjusted conversion rate		30.3431
Conversion of preferred units (in shares)		735,758
Number of shares issued (in shares)		0	516,639
Subordinated Units
Class of Stock [Line Items]
Adjusted conversion rate		39.7427
Conversion of preferred units (in shares)		963,681
Series B Cumulative Convertible Preferred Units
Class of Stock [Line Items]
Partners' equity, preferred units, outstanding (in shares)		14,711,000		14,711,000
Preferred units distribution rate		7.00%
Shares, price per share (in dollars per share)	$ 20.3926
Proceeds from issuance of convertible preferred stock	$ 300,000
Minimum underlying value for conversion trigger		$ 10,000
Preferred units, outstanding value		$ 298,361		$ 298,361
Accrued distributions				$ 5,300
Series B Cumulative Convertible Preferred Units | Noble Acquisition
Class of Stock [Line Items]
Number of shares issued (in shares)	14,711,219