Income Taxes (Schedule Of Effective Income Tax Rates Different From Statutory Federal Income Tax Rates) (Details)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Income Taxes [Abstract]
Statutory federal income tax rate	35.00%	35.00%	35.00%
State income taxes, net of federal income tax benefit	0.10%	0.20%	0.30%
Domestic production exclusion	(2.30%)	(2.50%)	(2.00%)
Tax-exempt investment income	0.00%	0.00%	(0.10%)
Other	(0.20%)	(0.40%)	(0.30%)
Effective income tax rate	32.60%	32.30%	32.90%