Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2016	Dec. 31, 2015
Statement of Financial Position [Abstract]
Common stock, par value (in dollars per share)	$ 0.005	$ 0.005
Common stock, shares authorized (in shares)	1,000,000,000	1,000,000,000
Common stock, shares issued (in shares)	74,801,825	73,107,848
Common stock, shares outstanding (in shares)	71,605,708	70,060,208