Retirement Plans (Schedule of Benefit Obligation, Fair Value of Assets, and Funded Status of the Plans) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
UNITED STATES
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation at beginning of year	$ 18,925	$ 16,112
Service cost	38	23	$ 33
Interest cost	742	771	707
Actuarial (gain) loss	(1,148)	2,753
Benefits paid	(798)	(734)
Benefit obligation at end of year	17,759	18,925	16,112
Fair value of assets at beginning of year	15,205	15,039
Actual gain (loss) on plan assets	(172)	601
Employer contribution	0	299
Fair value of assets at end of year	14,235	15,205	15,039
Funded status at end of year	(3,524)	(3,720)
Amounts recognized in the consolidated balance sheet consist of: Other long-term liabilities	(3,524)	(3,720)
Amounts recognized in accumulated other comprehensive income consist of: Net loss	3,993	4,429
Amounts recognized in accumulated other comprehensive income consist of: Prior service cost	0	3
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), before Tax, Total	3,993	4,432
UNITED KINGDOM
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation at beginning of year	8,797	8,450
Interest cost	295	360	348
Actuarial (gain) loss	(416)	883
Benefits paid	(339)	(397)
Foreign currency exchange rate changes	(475)	(499)
Benefit obligation at end of year	7,862	8,797	8,450
Fair value of assets at beginning of year	6,757	6,769
Actual gain (loss) on plan assets	307	502
Employer contribution	302	284
Foreign currency exchange rate changes	(366)	(401)
Fair value of assets at end of year	6,661	6,757	$ 6,769
Funded status at end of year	(1,201)	(2,040)
Amounts recognized in the consolidated balance sheet consist of: Other long-term liabilities	(1,201)	(2,040)
Amounts recognized in accumulated other comprehensive income consist of: Net loss	706	1,413
Amounts recognized in accumulated other comprehensive income consist of: Prior service cost	85	112
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), before Tax, Total	$ 791	$ 1,525