Carrying And Estimated Fair Value Of Other Financial Instruments (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Carrying Amounts and Fair Values of Financial Instruments or Liabilities [Line Items]
Acquisition-related contingent consideration, including current portion, Carrying Amount	$ 6,338	[1]	$ 13,329	[1]
Long-term debt, including current portion, Carrying Amount	711,000		717,000
Total, Carrying Amount	717,338		730,329
Acquisition-related contingent consideration, including current portion, Estimated Fair Value	6,338	[1]	13,329	[1]	16,426
Long-term debt, including current portion, Estimated Fair Value	735,000		752,750
Total, Estimated Fair Value	$ 741,338		$ 766,079

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