Retirement Benefits	12 Months Ended
Dec. 31, 2012
Compensation and Retirement Disclosure [Abstract]
Retirement Benefits Disclosure	25. Retirement benefits The Company makes contributions to defined contribution retirement plans that together cover substantially all employees. The level of the Company's contribution is fixed at a set percentage of employee's pay. Company contributions to personal defined contribution pension plans totaled $46.4 million, $44.4 million and $31.8 million for the years to December 31, 2012, 2011 and 2010, respectively, and were charged to operations as they became payable.

The entire disclosure for pension and other postretirement benefits.

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