Fair Value Measurements (Schedule Of Assets And Liabilities Carried At Fair Value Measured On A Recurring Basis) (Details) (Fair Value, Measurements, Recurring [Member], USD $) In Thousands, unless otherwise specified	Mar. 31, 2015		Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	$ 368,894	[1]	$ 432,056	[1]
Restricted cash	6,424	[2]	6,474	[2]
Deferred compensation plan assets	6,867	[3]	3,139	[3]
Total	382,185		441,669
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	368,894	[1]	432,056	[1]
Restricted cash	6,424	[2]	6,474	[2]
Deferred compensation plan assets	6,867	[3]	3,139	[3]
Total	382,185		441,669
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0	[1]	0	[1]
Restricted cash	0	[2]	0	[2]
Deferred compensation plan assets	0	[3]	0	[3]
Total	0		0
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0	[1]	0	[1]
Restricted cash	0	[2]	0	[2]
Deferred compensation plan assets	0	[3]	0	[3]
Total	0		0
Money Market Funds [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	$ 155,700		$ 156,700

[1] Cash and cash equivalents include money market funds with original maturity dates of three months or less, which are Level 1 assets. At March 31, 2015 and December 31, 2014, we had $155.7 million and $156.7 million, respectively, in money market funds.

[2] Restricted cash is classified as “Prepaid expenses and other” in the Condensed Consolidated Balance Sheets.

[3] Deferred compensation plan assets are classified as "Other assets" in the Condensed Consolidated Balance Sheets.