Common Stock (Details) shares in Thousands		12 Months Ended
	Jun. 19, 2015	Dec. 31, 2016 item $ / shares shares	Dec. 31, 2015 item $ / shares shares
Common Stock.
Authorized common stock (in shares)		750,000	750,000
Common stock, par value (in dollars per share) | $ / shares		$ 0.0001	$ 0.0001
Common stock outstanding (in shares)		52,665	50,346
Number of votes | item		1	1
Stock split conversion	0.6135