Significant Accounting Policies and Recently Issued Accounting Standards (Narrative) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2015 USD ($) segment item	Dec. 31, 2014 USD ($)
Accounting Policies
Bad debt expense	$ 2,168	$ 2,220
Write-offs, net of recoveries and other adjustments	1,989	$ 2,206
Cash overnight holdings	$ 66,722
Amortization threshold percentage	10.00%
Number of operating segments | segment	2
Series A
Accounting Policies
Common stock, voting rights, number of votes | item	1
Series B
Accounting Policies
Common stock, voting rights, number of votes | item	10
RSUs
Accounting Policies
Vested RSUs are redemption percentage of common stock	60.00%
Vested RSUs are redemption percentage of cash	40.00%
Vesting period	3 years