Partners' Capital, Equity and Incentive Compensation Plans (Details) - Class A Common Stock - Underwritten Offering - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended
	Feb. 28, 2019	Mar. 31, 2019
Partners Capital And Distributions [Line Items]
Shares under underwritten offering	7,762,500
Shares issued	4,000,000
Common Stock, Capital Shares Reserved for Future Issuance	3,762,500
Share Price	$ 41.50
Proceeds From Issuance Of Common Stock	$ 159	$ 148