Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Preferred stock, par value (in dollars per shares)	$ 0.001	$ 0.001
Preferred stock, authorized (in shares)	25,000,000	25,000,000
Preferred stock, Issued (in shares)	0	0
Preferred stock, outstanding (in shares)	0	0
Common stock, par value (in dollars per shares)	$ 0.001	$ 0.001
Common stock, authorized (in shares)	475,000,000	475,000,000
Common stock, issued (in shares)	58,013,144	58,910,282
Common stock, outstanding (in shares)	58,013,144	58,910,282