Income Taxes (Reconciliation Of Provision For Income Taxes) (Details)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Taxes [Abstract]
Consolidated tax provision at federal statutory rate	35.00%	35.00%	35.00%
State income tax provisions, net of federal income tax benefit	8.70%	1.60%	(2.70%)
Noncontrolling interest			(0.60%)
Tax reserve adjustment	(0.30%)	6.90%	(1.10%)
Domestic production activities deduction		(8.70%)
Changes in certain deferred tax balances	0.80%	(14.10%)	(4.00%)
IRS audit adjustments			3.20%
Federal research and development credit	1.50%	(3.30%)	(3.20%)
Non-deductible transaction costs	0.40%	1.00%	2.00%
All other, net	(0.30%)	0.30%	0.40%
Effective tax rate	45.80%	18.70%	29.00%