Consolidated Statements of Stockholders' Equity (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Statement Of Stockholders Equity [Abstract]
Common stock issued, per share	$ 92.2	$ 28.25	$ 28.76
Common stock initial public offering issuance costs	$ 6,367	$ 584	$ 305
Common stock issued private placement, per share	$ 92.2		$ 28.76