Income Taxes (Reconciliation Of Provision For Income Taxes And The Amount Computed Using The Federal Statutory Rate) (Details) (USD $) In Thousands	12 Months Ended
Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Income Taxes [Abstract]
Income tax provision at federal statutory rate	$ 612,347	$ 560,616	$ 347,497
States, net of federal benefit and Puerto Rico	30,865	28,968	12,412
Tax exempt investment income	(23,776)	(21,327)	(21,253)
Nondeductible executive compensation	12,655	55	30
Contingent tax benefits	0	(16,781)	0
Other, net	18,081	10,554	7,008
Provision for income taxes	$ 650,172	$ 562,085	$ 345,694

The provision for income taxes reflects the estimated impact from new limitations on the deductibility of annual compensation in excess of $500,000 per employee as mandated by the Health Insurance Reform Legislation

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The sum of the current income tax expense or benefit and the deferred income tax expense or benefit pertaining to continuing operations.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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-Publisher FASB

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The portion of the difference, between total income tax expense or benefit as reported in the Income Statement for the year/accounting period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations, that is attributable to all other items not otherwise listed in the existing taxonomy.

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The portion of the difference, between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations, that is attributable to state and local income tax expense or benefit.

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The portion of the difference, between total income tax expense or benefit as reported in the Income Statement and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations, that is attributable to changes in other income tax contingencies, whether recorded or adjusted, during the period not otherwise listed in the existing taxonomy.

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to income that is exempt from income taxes under enacted tax laws.

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