Income (Loss) Per Common Share - Basic Weighted Average Common Shares Outstanding to Diluted Weighted Average Common Shares Outstanding (Detail) - shares shares in Thousands		3 Months Ended
		Mar. 31, 2017	Mar. 31, 2016
Earnings Per Share [Abstract]
Weighted average common shares outstanding – basic	[1]	244,652	166,803
Effect of dilutive securities:
Director and employee PSUs and RSUs		151	0
Weighted average common shares outstanding – diluted		244,803	166,803

[1] 2017 includes common stock issued in connection with the exchange of 77.0 million shares for all outstanding Memorial common stock on September 16, 2016.