Employee Benefits Weighted-average assumptions used to determine the net periodic benefit cost (Details)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
U.K. [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Discount rate	4.45%	4.80%
Expected return on plan assets	6.30%	6.30%
Rate of compensation increase		3.55%	4.00%
U.K. [Member] | Minimum [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Discount rate			5.30%
Expected return on plan assets			3.20%
Rate of compensation increase	3.25%
U.K. [Member] | Maximum [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Discount rate			5.50%
Expected return on plan assets			7.20%
Rate of compensation increase	3.85%
U.S. [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Expected return on plan assets	8.80%	8.80%	8.80%
U.S. [Member] | Minimum [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Discount rate	3.73%	4.33%	4.35%
U.S. [Member] | Maximum [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Discount rate	4.05%	4.60%	5.34%
Other [Member] | Minimum [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Discount rate	3.25%	4.40%	4.70%
Expected return on plan assets	4.60%	4.90%	4.90%
Rate of compensation increase	2.25%	2.25%	2.00%
Other [Member] | Maximum [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Discount rate	3.89%	4.94%	5.45%
Expected return on plan assets	6.50%	6.75%	7.00%
Rate of compensation increase	3.50%	3.50%	3.50%