Represents the number of years the acquired entity is in existence as of the date of the acquisition.

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The business acquisition costs related to contract terminations and other expenses.

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The value of other real estate acquired in a business combination.

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The amount of LHFI, excluding covered loans acquired in a business combination.

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The portion of business combination expenses related to the termination of employees resulting from the combination.

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The total transaction costs of a business acquisition.

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Business combination increase decrease in acquired non covered loans as measurement period adjustment during the period.

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Business combination increase decrease in deferred tax asset as measurement period adjustment during the period.

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Business combination increase decrease in other real estate as measurement period adjustment during the period.

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Business combination increase decrease in acquired premises and equipment as measurement period adjustment during the period.

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Refers to issued value of preferred stock associated with warrant under capital purchase program.

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Number of markets entered due to acquisition.

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Number of shares of equity interests issued or issuable in a proposed business acquisition.

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No definition available.

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The per share value of equity issued per share of the business to be acquired.

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No definition available.

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Value of equity interests (such as common shares, preferred shares, or partnership interest) issued or issuable to acquire the entity.

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Amount of assets acquired at the acquisition date.

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Amount of currency on hand as well as demand deposits with banks or financial institutions, acquired at the acquisition date. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount of investments in debt and equity securities, including, but not limited to, held-to-maturity, trading and available-for-sale expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of other assets expected to be realized or consumed before one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of other liabilities due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.

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The amount of financial liabilities assumed (as defined) which have been recognized as of the acquisition date.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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Amount of liabilities assumed at the acquisition date.

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Amount of other liabilities due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of other assets expected to be realized or consumed after one year or the normal operating cycle, if longer, acquired at the acquisition date.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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Fair value at acquisition-date of the equity interest in the acquiree held by the acquirer, immediately before the acquisition date for businesses combined in stages.

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The total fair value for all investments, comprising or included in the major category, of those certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments) for which the entity has intentions to sell or liquidate, but the specific assets for sale or liquidation have not been identified (for example, the entity intends to sell $10,000,000 of its investments in private equity funds, but the individual investments to be sold have not been identified).

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase (decrease) of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase (decrease) from foreign currency translation adjustments and purchase accounting adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Fair value of share-based compensation granted to nonemployees as payment for services rendered or acknowledged claims.

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The weighted average of per share prices paid for shares purchased on the open market for issuance to employees under the plan.

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Value transferred from mortgage loans to real estate owned (REO) in noncash transactions.

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Business Combinations, BancTrust Financial Group (Details) (USD $)	3 Months Ended	12 Months Ended	0 Months Ended	3 Months Ended	12 Months Ended
	Mar. 31, 2014	Dec. 31, 2014	Feb. 15, 2013	Dec. 31, 2013	Dec. 31, 2013	Dec. 31, 2012
Business Acquisition [Line Items]
Decrease in goodwill with a corresponding increase in deferred tax asset as measurement period adjustment	$ 7,400,000us-gaap_GoodwillPeriodIncreaseDecrease
Assets [Abstract]
Total Assets		0		1,845,543,000	1,845,543,000	234,960,000
Liabilities [Abstract]
Total Liabilities		0		1,821,066,000	1,821,066,000	209,322,000
Goodwill		365,500,000us-gaap_Goodwill		372,851,000us-gaap_Goodwill	372,851,000us-gaap_Goodwill	291,104,000us-gaap_Goodwill
Amortization period of acquired intangible asset		20 years
BancTrust Financial Group, Inc. [Member]
Business Acquisition [Line Items]
Age of acquired entity			26 years
Preferred stock and warrants repurchased			50,000,000
Issued value of preferred stock associated warrant under capital purchase program			52,600,000
Equity issued, per share of acquired company (in shares)			0.125
Decrease in acquired non covered loans as measurement period adjustment				6,800,000	6,800,000
Decrease in Premises and equipment as measurement period adjustment					627,000
Decrease in other real estate as measurement period adjustment					2,600,000
Increase in deferred tax asset as measurement period adjustment					3,400,000
Increase in goodwill as measurement period adjustment					6,300,000
Transfer to other real estate as measurement period adjustment					1,600,000
Assets [Abstract]
Cash and due from banks			141,616,000
Securities available for sale			528,016,000
Loans held for sale			1,050,000
Acquired noncovered loans			944,235,000
Premises and equipment, net			54,952,000
Identifiable intangible assets			33,498,000
Other real estate			40,103,000
Other assets			109,423,000
Total Assets			1,852,893,000
Liabilities [Abstract]
Deposits			1,740,254,000
Other borrowings			64,051,000
Other liabilities			16,761,000
Total Liabilities			1,821,066,000
Net identified assets acquired at fair value			31,827,000
Goodwill			74,247,000
Equity issued (in shares)			2,240,000
Business acquisition, equity issued, value assigned			53,500,000
Business acquisition, closing stock price (in dollars per share)			$ 23.83
Number of markets entered due to acquisition		15
Amortization period of acquired intangible asset		10 years
Net assets acquired at fair value			106,074,000
Business acquisition, total transaction expenses					9,400,000
Business acquisition, severance expense					1,400,000
Business acquisition, contract termination and other expenses					$ 7,900,000