Debt And Credit Agreements (Schedule Of Borrowings Under Credit Agreement At Various Indebtedness To Adjusted EBITDA Levels) (Details)	12 Months Ended
	Dec. 31, 2015
Line of Credit Facility [Line Items]
Credit Spread Over LIBOR	1.75%
Indebtedness-To-Adjusted EBITDA Ratio Greater Than 2.0x But Less Than Or Equal To 3.0x [Member]
Line of Credit Facility [Line Items]
Credit Spread Over LIBOR	2.00%
Commitment Fee	0.35%
Indebtedness-To-Adjusted EBITDA Ratio Greater Than 1.0x But Less Than Or Equal To 2.0x [Member]
Line of Credit Facility [Line Items]
Credit Spread Over LIBOR	1.75%
Commitment Fee	0.30%
Indebtedness-To-Adjusted EBITDA Ratio Less Than Or Equal To 1.0x [Member]
Line of Credit Facility [Line Items]
Indebtedness-to-Adjusted EBITDA Ratio	1.0
Credit Spread Over LIBOR	1.50%
Commitment Fee	0.25%
Minimum | Indebtedness-To-Adjusted EBITDA Ratio Greater Than 2.0x But Less Than Or Equal To 3.0x [Member]
Line of Credit Facility [Line Items]
Indebtedness-to-Adjusted EBITDA Ratio	2.0
Minimum | Indebtedness-To-Adjusted EBITDA Ratio Greater Than 1.0x But Less Than Or Equal To 2.0x [Member]
Line of Credit Facility [Line Items]
Indebtedness-to-Adjusted EBITDA Ratio	1.0
Maximum | Indebtedness-To-Adjusted EBITDA Ratio Greater Than 2.0x But Less Than Or Equal To 3.0x [Member]
Line of Credit Facility [Line Items]
Indebtedness-to-Adjusted EBITDA Ratio	3.0
Maximum | Indebtedness-To-Adjusted EBITDA Ratio Greater Than 1.0x But Less Than Or Equal To 2.0x [Member]
Line of Credit Facility [Line Items]
Indebtedness-to-Adjusted EBITDA Ratio	2.0