Other Current Assets and Other Current Liabilities (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Other current assets [Abstract]
Revenue recognized in excess of billings, net of reserves of $1,994 and $2,249, respectively	$ 12,803	$ 12,069
Other non-trade receivables	367	426
Other current assets	14	11
Other current assets, Total	13,184	12,506
Revenue recognized in excess of billings, reserves	1,994	2,249
Other current liabilities [Abstract]
Customer deposits	3,207	2,697
Acquisition obligations	1,389	1,967
Accrued taxes	24	918
Other liabilities	2,775	2,623
Total other current liabilities	$ 7,395	$ 8,205