Employee Benefit Plans Schedule of Net Funded Status (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
U.S.
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Service cost	$ 59	$ 64	$ 59
Interest cost	555	519	513
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	9,290
Expected return on assets	739	623	576
Defined Benefit Plan, Fair Value of Plan Assets	9,642	9,290
Other liabilities	5,322	2,310
UK
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Service cost	0	0	0
Interest cost	2,204	2,046	2,371
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	30,151
Expected return on assets	1,861	1,661	1,680
Defined Benefit Plan, Fair Value of Plan Assets	30,010	30,151
Other liabilities	20,984	19,878
Change In Benefit Obligation | U.S.
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Projected benefit obligation at beginning of year	11,600	13,052
Service cost	59	64
Interest cost	555	519
Actuarial loss (gain)	3,021	(1,648)
Benefits paid	271	387
Currency translation adjustment	0	0
Projected benefit obligation at end of year	14,964	11,600
Accumulated benefit obligation at end of year	14,964	11,600
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Benefits paid	271	387
Change In Benefit Obligation | UK
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Projected benefit obligation at beginning of year	50,029	48,215
Service cost	0	0
Interest cost	2,204	2,046
Actuarial loss (gain)	4,046	732
Benefits paid	2,100	1,933
Currency translation adjustment	(3,185)	969
Projected benefit obligation at end of year	50,994	50,029
Accumulated benefit obligation at end of year	50,994	50,029
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Benefits paid	2,100	1,933
Change In Plan Assets | U.S.
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefits paid	271	387
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	9,290	7,897
Actual gain (loss) on plan assets	475	1,744
Expected return on assets	0	0
Employer contributions	208	75
Administrative expenses	60	39
Benefits paid	271	387
Currency translation adjustment	0	0
Defined Benefit Plan, Fair Value of Plan Assets	9,642	9,290
Funded status	(5,322)	(2,310)
Change In Plan Assets | UK
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefits paid	2,100	1,933
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	30,151	29,427
Actual gain (loss) on plan assets	1,150	(200)
Expected return on assets	1,861	1,661
Employer contributions	825	626
Administrative expenses	0	0
Benefits paid	2,100	1,933
Currency translation adjustment	(1,877)	570
Defined Benefit Plan, Fair Value of Plan Assets	30,010	30,151
Funded status	$ (20,984)	$ (19,878)