Employee Benefit Plans Amounts Recognized in Other Comprehensive Income (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
U.S.
Defined Benefit Plan Disclosure [Line Items]
Net actuarial (loss) gain	$ (3,344,000)	$ 2,730,000	$ (743,000)
Amortization of actuarial loss	0	292,000	252,000
Total recognized in other comprehensive income (loss)	(3,344,000)	3,022,000	(491,000)
Expected employer contributions in 2015	0
UK
Defined Benefit Plan Disclosure [Line Items]
Net actuarial (loss) gain	(2,746,000)	(972,000)	1,483,000
Amortization of actuarial loss	72,000	36,000	92,000
Total recognized in other comprehensive income (loss)	(2,674,000)	(936,000)	1,575,000
Expected employer contributions in 2015	$ 2,200,000