Financial Instruments (Schedule Of Carrying And Estimated Fair Value Of Other Financial Instruments) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011		Dec. 31, 2010		Dec. 31, 2009
Financial Instruments [Abstract]
Acquisition-related contingent consideration, including current portion, Carrying Amount	$ 14,990	[1]	$ 19,864	[1]
Acquisition-related contingent consideration, including current portion, Estimated Fair Value	14,990	[1]	19,864	[1]
Long-term debt, including current portion, Carrying Amount	814,885	[2]	810,841	[2]
Long-term debt, including current portion, Estimated Fair Value	882,277	[2]	847,248	[2]
Total, Carrying Amount	829,875		830,705
Total, Estimated Fair Value	897,267		867,112
Equity component of Convertible Notes	$ 18,019		$ 18,019

[1] The short-term portion is included in "Accounts payable, accrued expenses and other." The long-term portion is included in "Other liabilities."

[2] Carrying amount includes the equity component of Convertible Notes recorded in "Additional paid-in capital" of $18.0 million.