Condensed Consolidated Balance Sheets Parenthetical - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Accounts receivable, allowances	$ 2,040	$ 1,943
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	1,000	1,000
Preferred stock, shares issued (in shares)	0	0
Preferred Stock, Shares Outstanding	0	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	70,000,000	70,000,000
Common stock, shares issued (in shares)	39,733,000	39,712,000
Common stock, shares outstanding (in shares)	39,733,000	39,712,000