Loans, Impaired (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended	12 Months Ended
Sep. 30, 2012	Dec. 31, 2011
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	$ 67,000	$ 64,297
Recorded Investment With No Allowance	26,325	19,298
Recorded Investment With Allowance	31,170	35,400
Recorded Investment in Impaired Loans	57,495	54,698
Related Allowance	3,278	4,797
Average Outstanding Impaired Loans	49,417	49,307
Real Estate Loans - Construction and land development [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	28,090	28,721
Recorded Investment With No Allowance	12,832	14,484
Recorded Investment With Allowance	7,437	6,098
Recorded Investment in Impaired Loans	20,269	20,582
Related Allowance	1,821	3,264
Average Outstanding Impaired Loans	13,806	17,848
Real Estate Loans - Single-family residential [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	29,652	26,382
Recorded Investment With No Allowance	5,193	969
Recorded Investment With Allowance	23,416	24,719
Recorded Investment in Impaired Loans	28,609	25,688
Related Allowance	1,343	1,427
Average Outstanding Impaired Loans	28,620	25,102
Real estate loans - Commercial [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	7,903	7,717
Recorded Investment With No Allowance	6,953	3,845
Recorded Investment With Allowance	317	3,139
Recorded Investment in Impaired Loans	7,270	6,984
Related Allowance	114	77
Average Outstanding Impaired Loans	5,565	4,518
Real Estate Loans - Multifamily and farmland [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	200	209
Recorded Investment With No Allowance	200	0
Recorded Investment With Allowance	0	209
Recorded Investment in Impaired Loans	200	209
Related Allowance	0	1
Average Outstanding Impaired Loans	201	214
Total impaired real estate loans [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	65,845	63,029
Recorded Investment With No Allowance	25,178	19,298
Recorded Investment With Allowance	31,170	34,165
Recorded Investment in Impaired Loans	56,348	53,463
Related Allowance	3,278	4,769
Average Outstanding Impaired Loans	48,192	47,682
Commercial (not secured by real estate) [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	1,155	1,111
Recorded Investment With No Allowance	1,117	0
Recorded Investment With Allowance	0	1,083
Recorded Investment in Impaired Loans	1,117	1,083
Related Allowance	0	26
Average Outstanding Impaired Loans	1,187	1,485
Consumer loans (not secured by real estate) [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	0	157
Recorded Investment With No Allowance	30	0
Recorded Investment With Allowance	0	152
Recorded Investment in Impaired Loans	30	152
Related Allowance	0	2
Average Outstanding Impaired Loans	$ 38	$ 140

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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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=7512638&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=7512638&loc=d3e5258-111524

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 14A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=7512638&loc=SL6953550-111524

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