CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
ASSETS
Allowance for loan losses	$ 257,738	$ 261,679
Premises and equipment, accumulated depreciation	$ 88,826	$ 85,409
STOCKHOLDERS' EQUITY
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized	200,000,000us-gaap_CommonStockSharesAuthorized	200,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued	164,151,409us-gaap_CommonStockSharesIssued	163,772,218us-gaap_CommonStockSharesIssued
Common stock, shares outstanding	143,820,549us-gaap_CommonStockSharesOutstanding	143,582,229us-gaap_CommonStockSharesOutstanding
Treasury stock, shares	20,330,860us-gaap_TreasuryStockShares	20,189,989us-gaap_TreasuryStockShares

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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A valuation allowance for financing receivables that are expected to be uncollectible.

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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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