Statements Of Consolidated Comprehensive Income (Parenthetical) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Statement of Income and Comprehensive Income [Abstract]
Unrealized gain (loss) on available-for-sale security, deferred tax	$ 82	$ 10	$ 37	$ 14
Amortization of actuarial loss included in expense, deferred tax	$ 1,903	$ 941	$ 3,761	$ 1,952