Income Taxes (Reconciliation Of Provision For Income Taxes) (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Income Taxes [Abstract]
Consolidated tax provision at federal statutory rate (in hundredths)	35.00%	35.00%	35.00%	35.00%
State income tax provisions, net of federal income tax benefit (in hundredths)	31.40%	1.10%	7.80%	1.10%
Tax reserve adjustment (in hundredths)	(15.90%)	5.50%	(3.70%)	0.60%
Domestic production activities deduction (in hundreths)	15.80%	(16.90%)	3.60%	(5.30%)
Changes in certain deferred tax balances (in hundredths)	(9.50%)		6.20%	(1.70%)
Federal research and development credit (in hundreths)	5.40%	(7.80%)	1.10%	(2.40%)
All other, net (in hundredths)	0.90%	2.00%	(0.30%)	0.60%
Effective tax rate (in hundredths)	63.10%	18.90%	49.70%	27.90%