Description of Business and Summary of Significant Accounting Policies (Accounts Receivables and Allowances) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Accounts, Notes, Loans and Financing Receivable [Line Items]
Document Period End Date			Sep. 30, 2015
Accounts receivable	$ 47,166		$ 47,166		$ 41,100
Allowance for doubtful accounts	2,406		2,406		$ 1,619
Deferred revenue included in accounts receivables	6,300		6,300
Provision for doubtful accounts	1,649	$ 336	1,950	$ 1,083
Allowance for Doubtful Accounts Receivable, Write-offs			1,200
Billed Revenues [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	39,300		39,300
Unbilled Revenues [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	$ 10,300		$ 10,300
Maximum [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Delivery term for contractual elements of revenue arrangements			18 months