Business Acquisitions and Divestitures Fair Value of Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Thousands	Oct. 31, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Goodwill		$ 13,823	$ 11,810	$ 13,036
Lavante [Member]
Business Acquisition [Line Items]
Cash and cash equivalents	$ 28
Account receivables	207
Other Current Assets	92
Goodwill	2,146
Intangible Assets	6,178
Fixed Assets	98
Total Assets	8,749
Accounts payable	121
Deferred revenue	370
Other current liabilities	757
Total Liabilities	1,248
Total purchase price	$ 3,669