Income Taxes (Reconciliation Of Effective Income Tax Rate From Statutory Federal Income Tax Rate) (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%
Valuation allowance	3.00%	(37.20%)	0.50%
Transaction costs		(10.70%)
State income taxes, net of federal benefit and tax credits	(4.60%)	7.80%	1.80%
Permanent differences	5.40%	(7.80%)	0.80%
Domestic production activities	(13.60%)		(1.80%)
Federal research and experimentation credits	(5.30%)	5.50%	(0.40%)
Tax effects of foreign activities	1.70%	14.10%	(1.10%)
Tax-exempt income	(0.30%)	1.80%	(1.80%)
Provision to return adjustments	2.50%	1.70%	0.10%
Non-deductible compensation	3.00%	(2.20%)
Tax exposure reserve	(19.70%)	0.20%	(1.70%)
Other	(0.60%)	(3.30%)	0.70%
Effective income tax rate	6.50%	4.90%	32.10%