CONSOLIDATED STATEMENT OF CHANGESIN SHAREHOLDERS’ EQUITY (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Exercise of stock options, shares tendered in payment of exercise price		196,518
Shares paid for tax withholding for share-based compensation	901,691
Shares surrendered for tax withholding	$ 2,038
Preferred Stock
Underwriting discount and expenses	$ 723	$ 1,972	$ 2,531
Option
Exercise of stock options, shares tendered in payment of exercise price	1,129,195		43,535
Warrant
Exercise of stock options, shares tendered in payment of exercise price	846,789	196,518