Loans Held for Investment (LHFI) and Allowance for Loan Losses, excluding Covered Loans Part 1 (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Loan Portfolio [Abstract]
Loans Held For Investment, Excluding Covered Loans	$ 5,857,484	$ 6,060,242
Less Allowance For Loan Losses	89,518	93,510	103,662	94,922
Net LHFI, excluding covered loans	5,767,966	5,966,732
Loans and Leases Receivable, Other Information [Abstract]
Loans Held For Investment, Individually Evaluated For Impairment	110,458	142,923
Loans Held For Investment, Collectively Evaluated For Impairment	5,747,026	5,917,319
Total	5,857,484	6,060,242
Construction, Land Development And Other Financing Receivable [Member]
Loan Portfolio [Abstract]
Loans Held For Investment, Excluding Covered Loans	474,082	583,316
Loans and Leases Receivable, Other Information [Abstract]
Total	474,082	583,316
Residential Financing Receivable [Member]
Loan Portfolio [Abstract]
Loans Held For Investment, Excluding Covered Loans	1,760,930	1,732,056
Loans and Leases Receivable, Other Information [Abstract]
Total	1,760,930	1,732,056
Nonresidential Properties Financing Receivables [Member]
Loan Portfolio [Abstract]
Loans Held For Investment, Excluding Covered Loans	1,425,774	1,498,108
Loans and Leases Receivable, Other Information [Abstract]
Total	1,425,774	1,498,108
Other Real Estate Secured Financing Receivable [Member]
Loan Portfolio [Abstract]
Loans Held For Investment, Excluding Covered Loans	204,849	231,963
Loans and Leases Receivable, Other Information [Abstract]
Total	204,849	231,963
Real Estate Secured Financing Receivable [Member] | Construction, Land Development And Other Financing Receivable [Member]
Loan Portfolio [Abstract]
Loans Held For Investment, Excluding Covered Loans	474,082	583,316
Less Allowance For Loan Losses	27,220	35,562	43,551
Loans and Leases Receivable, Other Information [Abstract]
Loans Held For Investment, Individually Evaluated For Impairment	40,413	57,831
Loans Held For Investment, Collectively Evaluated For Impairment	433,669	525,485
Total	474,082	583,316
Real Estate Secured Financing Receivable [Member] | Residential Financing Receivable [Member]
Loan Portfolio [Abstract]
Loans Held For Investment, Excluding Covered Loans	1,760,930	1,732,056
Less Allowance For Loan Losses	12,650	13,051	13,151
Loans and Leases Receivable, Other Information [Abstract]
Loans Held For Investment, Individually Evaluated For Impairment	24,348	30,313
Loans Held For Investment, Collectively Evaluated For Impairment	1,736,582	1,701,743
Total	1,760,930	1,732,056
Real Estate Secured Financing Receivable [Member] | Nonresidential Properties Financing Receivables [Member]
Loan Portfolio [Abstract]
Loans Held For Investment, Excluding Covered Loans	1,425,774	1,498,108
Less Allowance For Loan Losses	24,358	20,980	20,110
Loans and Leases Receivable, Other Information [Abstract]
Loans Held For Investment, Individually Evaluated For Impairment	23,981	29,013
Loans Held For Investment, Collectively Evaluated For Impairment	1,401,793	1,469,095
Total	1,425,774	1,498,108
Real Estate Secured Financing Receivable [Member] | Other Real Estate Secured Financing Receivable [Member]
Loan Portfolio [Abstract]
Loans Held For Investment, Excluding Covered Loans	204,849	231,963
Less Allowance For Loan Losses	3,079	1,582	1,631
Loans and Leases Receivable, Other Information [Abstract]
Loans Held For Investment, Individually Evaluated For Impairment	5,871	6,154
Loans Held For Investment, Collectively Evaluated For Impairment	198,978	225,809
Total	204,849	231,963
Commercial And Industrial Loans [Member]
Loan Portfolio [Abstract]
Loans Held For Investment, Excluding Covered Loans	1,139,365	1,068,369
Less Allowance For Loan Losses	15,868	14,775	16,275
Loans and Leases Receivable, Other Information [Abstract]
Loans Held For Investment, Individually Evaluated For Impairment	14,148	16,107
Loans Held For Investment, Collectively Evaluated For Impairment	1,125,217	1,052,262
Total	1,139,365	1,068,369
Consumer Loans Financing Receivable [Member]
Loan Portfolio [Abstract]
Loans Held For Investment, Excluding Covered Loans	243,756	402,165
Less Allowance For Loan Losses	3,656	5,400	7,246
Loans and Leases Receivable, Other Information [Abstract]
Loans Held For Investment, Individually Evaluated For Impairment	825	2,112
Loans Held For Investment, Collectively Evaluated For Impairment	242,931	400,053
Total	243,756	402,165
Other Loans Financing Receivable [Member]
Loan Portfolio [Abstract]
Loans Held For Investment, Excluding Covered Loans	608,728	544,265
Less Allowance For Loan Losses	2,687	2,160	1,698
Loans and Leases Receivable, Other Information [Abstract]
Loans Held For Investment, Individually Evaluated For Impairment	872	1,393
Loans Held For Investment, Collectively Evaluated For Impairment	607,856	542,872
Total	$ 608,728	$ 544,265