June 2012 Stock Sale (Details) (USD $)	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013 Piper transaction	Jun. 07, 2012 Piper	Jun. 05, 2012 Piper
Subsidiary, Sale of Stock [Line Items]
Revenue	$ 35,249,000	$ 33,260,000	$ 33,964,000	$ 29,784,000	$ 29,222,000	$ 26,696,000	$ 25,509,000	$ 24,519,000	$ 132,257,000	$ 105,946,000	$ 83,417,000
Gross Profit	26,077,000	25,898,000	25,004,000	22,528,000	22,064,000	20,252,000	19,232,000	19,116,000	32,750,000	25,282,000	18,746,000
Operating Expenses	27,217,000	28,116,000	27,524,000	27,018,000	27,761,000	27,185,000	24,819,000	22,790,000	109,875,000	102,555,000	83,087,000
Net income (loss)	(3,412,000)	(8,990,000)	5,670,000	(9,335,000)	(6,518,000)	(5,857,000)	(6,696,000)	(16,703,000)	(16,068,000)	(35,774,000)	(28,730,000)
Basic income (loss) per share (usd per share)	$ (0.05)	$ (0.14)	$ 0.09	$ (0.16)	$ (0.10)	$ (0.10)	$ (0.11)	$ (0.29)	$ (0.26)	$ (0.60)	$ (0.51)
Diluted income (loss) per share (usd per share)	$ (0.05)	$ (0.14)	$ 0.09	$ (0.16)	$ (0.10)	$ (0.10)	$ (0.11)	$ (0.29)
Prior Period Reclassification Adjustment					600,000
Common shares sold													400,000	2,700,000
Sale of common stock, price per share													$ 13.00	$ 13.00
Number of transactions												2
Gross proceeds												40,300,000
Legal fees									819,000			100,000
Professional fees												$ 200,000