Pension and Other Postretirement Benefit Plans (Details Textual) (Pension Benefits [Member]) In Thousands, unless otherwise specified	3 Months Ended		12 Months Ended
	Mar. 31, 2015 USD ($)	Mar. 31, 2015 GBP (£)	Dec. 31, 2014 USD ($)
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Contributions by Employer	$ 7,235	£ 4,896	$ 7,601