Income Taxes (Details 2) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Income Taxes
Expected income tax expense at statutory federal rate	$ 28,340	$ 37,073	$ 40,193
State and local taxes, net of federal tax effect	2,673	2,378	2,405
Tax exempt income (principally on BOLI)	(3,356)	(3,672)	(3,141)
Non-deductible ESOP compensation	2,187	3,936	2,958
Low income housing tax credit	(1,727)	(1,885)	(1,975)
Other, net	(237)	885	663
Total income tax expense	$ 27,880	$ 38,715	$ 41,103

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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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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 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 nondeductible expenses under enacted tax laws, or differences in the methodologies used to determine expense amounts for financial statements prepared in accordance with generally accepted accounting principles, not otherwise listed in the existing taxonomy.

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