Commitments and Contingencies (Narrative) (Details) $ in Thousands			12 Months Ended
	Jun. 10, 2013 Complaint	May. 01, 2013 Complaint	Dec. 31, 2015 USD ($) $ / Person	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Commitments and Contingencies [Line Items]
Class action complaints filed and consolidated | Complaint	12	12
Rent expense, operating leases			$ 6,500	$ 6,300	$ 6,500
Operating Leases, Rent Expense, Sublease Rentals			580	381	$ 55
Self-insured health insurance, liability			$ 276	$ 250
Maximum [Member]
Commitments and Contingencies [Line Items]
Self-insured health insurance limit, per person | $ / Person			120,000
Self-insured health Insurance, aggregate liability based on participants and claims (percentage)			125.00%
Self-insured health insurance, estimated cumulative liability for annual contract			$ 2,900
Computer equipment | Minimum [Member]
Commitments and Contingencies [Line Items]
Term of Lease			3 years
Computer equipment | Maximum [Member]
Commitments and Contingencies [Line Items]
Term of Lease			5 years