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]	3 Months Ended
	Mar. 31, 2016
Auction Rate Equity Securities [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Discount rate range, low end	2.00%
Discount rate range, high end	12.20%
Workout period range, low end	1 year
Workout period range, high end	3 years
Discount rate, weighted average	6.50%
Weighted average workout period	2 years 4 months 24 days
Auction Rate Municipal Securities [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Discount rate range, low end	0.00%
Discount rate range, high end	11.30%
Workout period range, low end	1 year
Workout period range, high end	4 years
Discount rate, weighted average	5.20%
Weighted average workout period	2 years 1 month 6 days