Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Statement of Financial Position [Abstract]
Securities held to maturity, fair value	$ 1,468,258	$ 1,189,563
Unearned income on loans	$ 56,131	$ 55,051
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	20,000,000us-gaap_PreferredStockSharesAuthorized	20,000,000us-gaap_PreferredStockSharesAuthorized
Preferred stock, shares issued	110,877us-gaap_PreferredStockSharesIssued	110,877us-gaap_PreferredStockSharesIssued
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	500,000,000us-gaap_CommonStockSharesAuthorized	500,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued	175,450,303us-gaap_CommonStockSharesIssued	159,624,796us-gaap_CommonStockSharesIssued
Treasury stock, shares	1,458,045us-gaap_TreasuryStockShares	657,585us-gaap_TreasuryStockShares

Face amount or stated value per share of common stock.

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Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

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