Income Taxes (Schedule Of Company's Actual Income Tax Expense) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]
Computed “expected” tax expense	$ 133,690	$ 134,117	$ 138,774
Tax-exempt interest, net of cost to carry	(17,806)	(16,612)	(15,516)
State and local income taxes, net of federal tax benefit	7,613	7,836	7,692
Tax deductible dividends on allocated shares held by the Company’s ESOP	(1,116)	(1,116)	(2,991)
Other	(2,165)	(1,995)	(790)
Total income tax expense	$ 120,216us-gaap_IncomeTaxExpenseBenefit	$ 122,230us-gaap_IncomeTaxExpenseBenefit	$ 127,169us-gaap_IncomeTaxExpenseBenefit

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(h))

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-Number 210

-Section 08

-Paragraph h

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-Name Accounting Standards Codification

-Glossary Income Tax Expense (or Benefit)

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-Name Accounting Standards Codification

-Topic 740

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-Section 50

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to deduction for dividend.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Topic 740

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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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