Organization and Business (Details) - USD ($) $ / shares in Units, $ in Millions	Apr. 11, 2016	Jan. 25, 2016	Jun. 30, 2016	Dec. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Common stock, shares authorized (in shares)			500,000,000	500,000,000
Common stock, par value (in dollars per share)			$ 0.01	$ 0.01
Common shares sold	25,875,000	21,275,000
Shares issued upon exercise of the underwriters' overallotment option	3,375,000	2,775,000
Net proceeds	$ 442.8	$ 321.1
Number of partnership units issued	25,875,000	21,275,000