Fair Value (Estimated Fair Values Of Assets And Liabilities Measured And Recorded At Fair Value On A Recurring Basis) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	$ 102.6	$ 131.8	$ 94.5
S And P Five Hundred Index Options [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	13.6	15.8	11.3
Unobservable Inputs	(a)	(a)
Fair Value Measurements Significant Assumptions	Various assumptions	Various assumptions
Fair Value Measurements Valuation Techniques	Black-Scholes option pricing model	Black-Scholes option pricing model
Index Based Interest Guarantees [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value	77.0	67.6	57.4
Fair Value Measurements Significant Assumptions	Expected future, Various assumptions	Expected future, Various assumptions
Fair Value Measurements Valuation Techniques	Discounted cash , Black-Scholes option pricing model	Discounted cash , Black-Scholes option pricing model
Index Based Interest Guarantees [Member] | Various Assumptions [Member] | Black Scholes Option Pricing Model [Member]
Unobservable Inputs	(a)	(a)
Index Based Interest Guarantees [Member] | Various Assumptions [Member] | Discounted Cash Flow [Member]
Unobservable Inputs	(b)	(b)
Index Based Interest Guarantees [Member] | Various Assumptions [Member] | Discounted Cash Flow [Member] | Maximum [Member]
Unobservable Inputs	36%	36%
Index Based Interest Guarantees [Member] | Various Assumptions [Member] | Discounted Cash Flow [Member] | Minimum [Member]
Unobservable Inputs	5%	5%
Index Based Interest Guarantees [Member] | Expected Future Option Purchase [Member] | Discounted Cash Flow [Member] | Maximum [Member]
Unobservable Inputs	3%	6%
Index Based Interest Guarantees [Member] | Expected Future Option Purchase [Member] | Discounted Cash Flow [Member] | Minimum [Member]
Unobservable Inputs	1%	1%
Commercial Mortgage Loans [Member]
Fair Value Measurements Significant Assumptions	Reduction on appraisal , Capitalization rate (c)	Reduction on appraisal , Capitalization rate (c)
Fair Value Measurements Valuation Techniques	Appraisals, Cash flows	Appraisals, Cash flows
Commercial Mortgage Loans [Member] | Reduction On Appraisal [Member] | Appraisals Member [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	56.0	68.7
Commercial Mortgage Loans [Member] | Reduction On Appraisal [Member] | Appraisals Member [Member] | Maximum [Member]
Unobservable Inputs	37%	13%
Commercial Mortgage Loans [Member] | Reduction On Appraisal [Member] | Appraisals Member [Member] | Minimum [Member]
Unobservable Inputs	0%	0%
Commercial Mortgage Loans [Member] | Capitalization Rate [Member] | CashFlowsMember [Member] | Maximum [Member]
Unobservable Inputs	16%	16%
Commercial Mortgage Loans [Member] | Capitalization Rate [Member] | CashFlowsMember [Member] | Minimum [Member]
Unobservable Inputs	7%	7%
Real Estate Owned [Member]
Fair Value Measurements Significant Assumptions	Reduction on appraisal	Reduction on appraisal
Fair Value Measurements Valuation Techniques	Appraisals	Appraisals
Real Estate Owned [Member] | Reduction On Appraisal [Member] | Appraisals Member [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	$ 10.3	$ 35.2
Real Estate Owned [Member] | Reduction On Appraisal [Member] | Appraisals Member [Member] | Maximum [Member]
Unobservable Inputs	11%	53%
Real Estate Owned [Member] | Reduction On Appraisal [Member] | Appraisals Member [Member] | Minimum [Member]
Unobservable Inputs	0%	0%