CONSOLIDATED STATEMENTS OF FINANCIAL CONDITION (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Held-to-maturity securities, fair value	2,131,371	1,811,122
Preferred stock, par value (in dollars per share)	1.00	1.00
Preferred stock, shares authorized	5,000,000us-gaap_PreferredStockSharesAuthorized	5,000,000us-gaap_PreferredStockSharesAuthorized
Common stock, par value (in dollars per share)	0.01	0.01
Common stock, shares authorized	200,000,000us-gaap_CommonStockSharesAuthorized	200,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued	166,494,888us-gaap_CommonStockSharesIssued	166,494,888us-gaap_CommonStockSharesIssued
Common stock, shares outstanding	99,940,399us-gaap_CommonStockSharesOutstanding	98,841,960us-gaap_CommonStockSharesOutstanding
Treasury stock, shares	66,554,489us-gaap_TreasuryStockShares	67,652,928us-gaap_TreasuryStockShares
Series C Preferred Stock
Preferred stock, shares authorized	150,000	150,000
Preferred stock, shares issued	135,000	135,000
Preferred stock, shares outstanding	135,000	135,000

Face amount or stated value per share of common stock.

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