Dispositions and Acquisitions - Acquisitions - Additional Information (Detail) $ in Thousands		3 Months Ended				4 Months Ended	9 Months Ended	12 Months Ended
	Sep. 16, 2016 USD ($) shares	Dec. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Business Acquisition [Line Items]
Merger-related expenses		$ 813	$ 33,791	$ 2,621	$ 0		$ 37,200	$ 0	$ 37,225	$ 0
Pro Forma Adjusted for Merger Expenses Incurred
Business Acquisition [Line Items]
Merger-related expenses									37,200
MRD
Business Acquisition [Line Items]
Business merger date								Sep. 16, 2016
Common stock issued in connection with exchange of outstanding shares | shares	77,042,749
Exchange ratio of common shares for acquired company	0.375
Fair value of outstanding debt	$ 1,204,449
Revenues						$ 146,600		$ 477,400
Net operating income						$ 94,900		$ 278,800
MRD | Pro Forma Adjustment
Business Acquisition [Line Items]
Merger-related expenses									$ 7,100