Other Real Estate and Covered Other Real Estate - Changes and Gains, Net on Other Real Estate, Excluding Covered Other Real Estate (Parenthetical) (Details) $ in Millions	Feb. 15, 2013 USD ($)
BancTrust Financial Group, Inc. [Member]
Other real estate, excluding covered other real estate [Line Items]
Business acquisition, covered other real estate acquired	$ 40.1

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration