Fair Value Of Financial Instruments (Quantitative Information related To The Significant Unobservable Inputs Utilized In Company's Level 3 Recurring Fair Value Measurements) (Details) - Discounted Cash Flow [Member]	12 Months Ended
	Dec. 31, 2015
Auction Rate Equity Securities [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Discount rate range, low end	2.30%
Discount rate range, high end	13.40%
Workout period range, low end	1 year
Workout period range, high end	3 years
Discount rate, weighted average	7.20%
Weighted average workout period	2 years 3 months 18 days
Auction Rate Municipal Securities [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Discount rate range, low end	0.30%
Discount rate range, high end	12.70%
Workout period range, low end	1 year
Workout period range, high end	4 years
Discount rate, weighted average	7.70%
Weighted average workout period	2 years 9 months 18 days