Portfolio Loans Not Covered by Loss Share ("Non-covered") - Summary of Non-covered Loans Individually Evaluated for Impairment by Category (Details) (USD $)	3 Months Ended	6 Months Ended	12 Months Ended	6 Months Ended	12 Months Ended	6 Months Ended	12 Months Ended	6 Months Ended	12 Months Ended	6 Months Ended	12 Months Ended	6 Months Ended	12 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2013	Jun. 30, 2013	Jun. 30, 2013 Non-Covered Loans	Dec. 31, 2012 Non-Covered Loans	Jun. 30, 2013 Non-Covered Loans Commercial & Industrial	Dec. 31, 2012 Non-Covered Loans Commercial & Industrial	Jun. 30, 2013 Non-Covered Loans Real Estate Commercial - Owner Occupied	Dec. 31, 2012 Non-Covered Loans Real Estate Commercial - Owner Occupied	Jun. 30, 2013 Non-Covered Loans Real Estate Commercial - Investor Owned	Dec. 31, 2012 Non-Covered Loans Real Estate Commercial - Investor Owned	Jun. 30, 2013 Non-Covered Loans Real Estate Construction and Land Development	Dec. 31, 2012 Non-Covered Loans Real Estate Construction and Land Development	Jun. 30, 2013 Non-Covered Loans Real Estate Residential	Dec. 31, 2012 Non-Covered Loans Real Estate Residential	Jun. 30, 2013 Non-Covered Loans Consumer & Other	Dec. 31, 2012 Non-Covered Loans Consumer & Other
Financing Receivable, Impaired [Line Items]
Troubled Debt Restructurings on Financing Receivables [Table Text Block]		no
Impaired Financing Receivable, Interest Income, Cash Basis Method	$ 9,000	$ 24,000
Unpaid Contractual Principal Balance			31,380,000	45,218,000	6,841,000	9,005,000	1,137,000	6,726,000	14,776,000	19,864,000	5,477,000	6,491,000	3,149,000	3,132,000	0	0
Recorded Investment With No Allowance			14,001,000	5,645,000	0	96,000	778,000	2,178,000	7,925,000	185,000	3,380,000	1,560,000	1,918,000	1,626,000	0	0
Recorded Investment With Allowance			12,598,000	33,082,000	6,788,000	8,838,000	0	3,594,000	4,069,000	16,577,000	1,145,000	3,135,000	596,000	938,000	0	0
Total Recorded Investment			26,599,000	38,727,000	6,788,000	8,934,000	778,000	5,772,000	11,994,000	16,762,000	4,525,000	4,695,000	2,514,000	2,564,000	0	0
Related Allowance			4,331,000	8,176,000	3,221,000	3,446,000	0	339,000	591,000	3,400,000	452,000	732,000	67,000	259,000	0	0
Average Recorded Investment			31,912,000	39,491,000	7,959,000	6,379,000	3,529,000	7,985,000	12,798,000	10,500,000	5,059,000	10,259,000	2,567,000	4,368,000	0	0
Impaired Financing Receivable, Interest Income, Accrual Method	$ 0

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

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Amount of investment in impaired financing receivables for which there is no related allowance for credit losses.

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Tabular disclosure of financing receivables and troubled debt restructurings.

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