Reinsurance (Narrative Details) (USD $)	Dec. 31, 2012	Dec. 31, 2011
Reinsurance [Line Items]
Statutory Financial Reinsurance	$ 6,300,000,000	$ 4,300,000,000
Statutory Reserves Related To Financial Requirements	1,522,100,000	1,277,200,000
Assets held in trust and held in custody	909,200,000	896,100,000
Benefit Of RGA Subsidiaries [Member]
Reinsurance [Line Items]
Assets held in trust and held in custody	2,140,700,000	1,534,000,000
Benefit Of Third Parties [Member]
Reinsurance [Line Items]
Assets held in trust and held in custody	$ 7,549,000,000	$ 2,144,600,000