CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
ASSETS
Non-covered loans, allowance for loan losses	$ 258,174	$ 241,930
Covered loans, allowance for loan losses	3,505	7,745
Premises and equipment, accumulated depreciation	$ 85,409	$ 69,768
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	163,772,218us-gaap_CommonStockSharesIssued	163,098,008us-gaap_CommonStockSharesIssued
Common stock, shares outstanding	143,582,229us-gaap_CommonStockSharesOutstanding	137,630,896us-gaap_CommonStockSharesOutstanding
Treasury stock, shares	20,189,989us-gaap_TreasuryStockShares	25,467,112us-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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