CONDENSED COMBINED STATEMENTS OF EQUITY $ in Thousands	USD ($)
Balance at Dec. 31, 2015	$ 2,304,519
Statement Of Stockholders Equity [Abstract]
Net income	33,699
Transactions with Parent, net	(23,693)
Balance at Mar. 31, 2016	2,314,525
Balance at Dec. 31, 2016	2,417,285
Statement Of Stockholders Equity [Abstract]
Net income	26,888
Transactions with Parent, net	(45,052)
Balance at Mar. 31, 2017	$ 2,399,121