Reinsurance Reinsurance (Details Textual) (Details) (USD $)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Premiums Receivable, Allowance for Doubtful Accounts	$ 245,000,000		$ 244,000,000
Life Insurance Recoveries on Ceded Reinsurance Contracts	215,000,000	232,000,000
Reinsurance Recoverables	23,139,000,000		23,330,000,000
Property and Casualty Ceded Losses which Reduce Losses and Loss Adjustment Expenses Incurred	105,000,000	133,000,000
Percentage of Stockholders' Equity to Credit Concentration Risk	10.00%
Individual Life [Member]
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Reinsurance Recoverables	0
Individual Life [Member] | Prudential [Member]
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Fair Value of Assets Held in Trust	0
Retirement Plans [Member]
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Reinsurance Recoverables	0
Retirement Plans [Member] | Mass Mutual [Member]
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Fair Value of Assets Held in Trust	$ 0