Long-Term Debt (Schedule Of Long-Term Debt) (Details) (USD $)																																								12 Months Ended		12 Months Ended										12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Nov. 30, 2007	Dec. 31, 2011 1.636 To 7.040% Fixed [Member]	Dec. 31, 2010 1.636 To 7.040% Fixed [Member]	Dec. 31, 2011 0.50 To 5.00% Fixed [Member]	Dec. 31, 2010 0.50 To 5.00% Fixed [Member]	Dec. 31, 2011 Statutory Trust I, 3 Month LIBOR Plus 3.25% [Member]		Dec. 31, 2010 Statutory Trust I, 3 Month LIBOR Plus 3.25% [Member]		Dec. 31, 2011 Statutory Trust II, 3 Month LIBOR Plus 3.15% [Member]		Dec. 31, 2010 Statutory Trust II, 3 Month LIBOR Plus 3.15% [Member]		Dec. 31, 2011 Statutory Trust III, 3 Month LIBOR Plus 2.00% [Member]		Dec. 31, 2010 Statutory Trust III, 3 Month LIBOR Plus 2.00% [Member]		Dec. 31, 2011 Statutory Trust IV, 3 Month LIBOR Plus 1.60% [Member]		Dec. 31, 2010 Statutory Trust IV, 3 Month LIBOR Plus 1.60% [Member]		Dec. 31, 2011 American Horizons Statutory Trust I, 3 Month LIBOR Plus 3.15% [Member]		Dec. 31, 2010 American Horizons Statutory Trust I, 3 Month LIBOR Plus 3.15% [Member]		Dec. 31, 2011 Statutory Trust V, 3 Month LIBOR Plus 1.435% [Member]		Dec. 31, 2010 Statutory Trust V, 3 Month LIBOR Plus 1.435% [Member]		Dec. 31, 2011 Statutory Trust VI, 3 Month LIBOR Plus 2.75% [Member]		Dec. 31, 2010 Statutory Trust VI, 3 Month LIBOR Plus 2.75% [Member]		Dec. 31, 2011 Statutory Trust VII, 3 Month LIBOR Plus 2.54% [Member]		Dec. 31, 2010 Statutory Trust VII, 3 Month LIBOR Plus 2.54% [Member]		Dec. 31, 2011 Pocahontas Capital Trust I, Fixed Rate Of 10.18% [Member]	Dec. 31, 2010 Pocahontas Capital Trust I, Fixed Rate Of 10.18% [Member]	Dec. 31, 2011 Pulaski Capital Trust I, Fixed Rate Of 10.875% [Member]	Dec. 31, 2010 Pulaski Capital Trust I, Fixed Rate Of 10.875% [Member]	Dec. 31, 2011 Statutory Trust VIII, 3 Month LIBOR Plus 3.50% [Member]		Dec. 31, 2010 Statutory Trust VIII, 3 Month LIBOR Plus 3.50% [Member]		Dec. 31, 2011 OMNI Trust I, 3 Month LIBOR Plus 3.30% [Member]		Dec. 31, 2011 OMNI Trust II, 3 Month LIBOR Plus 2.79% [Member]		Dec. 31, 2011 Maximum [Member] 1.636 To 7.040% Fixed [Member]	Dec. 31, 2011 Maximum [Member] 0.50 To 5.00% Fixed [Member]	Dec. 31, 2011 Minimum [Member] 1.636 To 7.040% Fixed [Member]	Dec. 31, 2011 Minimum [Member] 0.50 To 5.00% Fixed [Member]
Debt Instrument [Line Items]
Federal Home Loan Bank notes				$ 285,930,000	$ 269,237,000
Notes payable - Investment fund contributions						54,941,000	51,764,000
Junior subordinated debt			25,775,000					10,310,000	[1]	10,310,000	[1]	10,310,000	[1]	10,310,000	[1]	10,310,000	[1]	10,310,000	[1]	15,464,000	[1]	15,464,000	[1]	6,186,000	[1]	6,186,000	[1]	10,310,000	[1]	10,310,000	[1]	12,372,000	[1]	12,372,000	[1]	13,403,000	[1]	13,403,000	[1]		7,824,000		7,544,000	7,217,000	[1]	7,217,000	[1]	8,248,000	[1]	7,732,000	[1]
Total long-term debt	$ 452,733,000	$ 432,251,000
Long-term debt, fixed interest, percentage rate																																								10.18%		10.875%										7.04%	5.00%	1.636%	0.50%
Debt instrument maturity date period, (in years)																																																					40		7
LIBOR plus rate								3.25%				3.15%				2.00%				1.60%				3.15%				1.435%				2.75%				2.54%								3.50%				3.30%		2.79%
3-month LIBOR rate	0.58%

[1] The interest rate on the Company's long-term debt indexed to LIBOR is based on the 3-month LIBOR rate. At December 31, 2011, the 3-month LIBOR rate was 0.58%.