Consolidated Statements of Financial Condition (Unaudited) (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
ASSETS:
Held to maturity securities, fair value	$ 71,675	$ 75,342
SHAREHOLDERS' EQUITY:
Capital stock, par value (in dollars per share)	$ 1	$ 1
Capital stock, shares authorized (in shares)	150,000,000us-gaap_CommonStockSharesAuthorized	150,000,000us-gaap_CommonStockSharesAuthorized
Capital stock, shares issued (in shares)	98,964,052us-gaap_CommonStockSharesIssued	98,944,623us-gaap_CommonStockSharesIssued
Treasury stock, at cost (in shares)	4,008,458us-gaap_TreasuryStockShares	4,087,295us-gaap_TreasuryStockShares

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Face amount or stated value per share of common stock.

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Fair value of investments in debt securities classified as held-to-maturity.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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