Income Taxes (Reconciliation Of Income Taxes) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Components of Income Tax Expense (Benefit), Continuing Operations [Abstract]
Federal statutory rate	35.00%
Computed tax expense	$ 47,359	$ 85,785	$ 63,837
Tax-exempt interest income	(27,789)	(31,414)	(33,966)
Dividends received deduction	(1,482)	(1,704)	(1,463)
State tax expense (benefit)	1,918	1,299	(3,580)
Other, net	(1,607)	(31)	5,364
Total	$ 18,399	$ 53,935	$ 30,192

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The domestic federal statutory tax rate applicable under enacted tax laws to the Company's pretax income from continuing operations for the period. The "statutory" tax rate is the regular tax rate if there are alternative tax systems.

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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.

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-Glossary 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 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 the deduction for dividends paid or received under enacted tax laws.

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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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The sum of other amounts reflected in the reconciliation of the statutory tax provision (benefit) to the actual tax provision (benefit).

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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 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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