Income Taxes (Reconciliation Of Provision For Income Taxes) (Details)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Taxes [Abstract]
Consolidated tax provision at federal statutory rate (in hundredths)	35.00%	35.00%	35.00%
State income tax provisions, net of federal income tax benefit (in hundredths)	1.60%	(2.70%)	2.40%
Noncontrolling interest (in hundredths)		(0.60%)	(2.50%)
Tax reserve adjustment (in hundredths)	6.90%	(1.10%)	(5.40%)
Domestic production activities deduction (in hundreths)	(8.70%)
Changes in certain deferred tax balances (in hundredths)	(14.10%)	(4.00%)	3.10%
IRS audit adjustments (in hundredths)		3.20%
Federal research and development credit (in hundreths)	(3.30%)	(3.20%)
Non-deductible transaction costs (in hundreths)	1.00%	2.00%
All other, net (in hundredths)	0.30%	0.40%	0.40%
Effective tax rate (in hundredths)	18.70%	29.00%	33.00%