Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012		Dec. 31, 2011
Assets:
Total assets	$ 10,824		$ 73,620
Liabilities:
Total liabilities	729		752
Money market funds and open end mutual funds [Member]
Assets:
Money market funds and open-end mutual funds included in "Cash and cash equivalents"	3,428	[1]	68,651	[1]
Money market funds and open-end mutual funds in "Deferred charges and other assets"	11	[1]	12	[1]
Foreign currency forward contracts [Member]
Assets:
Foreign currency forward and option contracts	2,165	[2]	710	[2]
Equity investments held in a rabbi trust for the Deferred Compensation Plan [Member]
Assets:
Debt investments held in a rabbi trust for the Deferred Compensation Plan	3,146	[3]	2,817	[3]
Debt investments held in a rabbi trust for the Deferred Compensation Plan [Member]
Assets:
Debt investments held in a rabbi trust for the Deferred Compensation Plan	1,994	[3]	1,365	[3]
Guaranteed investment certificates [Member]
Assets:
Debt investments held in a rabbi trust for the Deferred Compensation Plan	80	[4]	65	[4]
Foreign currency option contracts [Member]
Liabilities:
Foreign currency forward and option contracts	729	[5]	752	[5]
Fair Value, Inputs, Level 1[Member]
Assets:
Total assets	8,579		72,845
Liabilities:
Total liabilities
Fair Value, Inputs, Level 1[Member] | Money market funds and open end mutual funds [Member]
Assets:
Money market funds and open-end mutual funds included in "Cash and cash equivalents"	3,428	[1]	68,651	[1]
Money market funds and open-end mutual funds in "Deferred charges and other assets"	11	[1]	12	[1]
Fair Value, Inputs, Level 1[Member] | Foreign currency forward contracts [Member]
Assets:
Foreign currency forward and option contracts		[2]
Fair Value, Inputs, Level 1[Member] | Equity investments held in a rabbi trust for the Deferred Compensation Plan [Member]
Assets:
Debt investments held in a rabbi trust for the Deferred Compensation Plan	3,146	[3]	2,817	[3]
Fair Value, Inputs, Level 1[Member] | Debt investments held in a rabbi trust for the Deferred Compensation Plan [Member]
Assets:
Debt investments held in a rabbi trust for the Deferred Compensation Plan	1,994	[3]	1,365	[3]
Fair Value, Inputs, Level 1[Member] | Guaranteed investment certificates [Member]
Assets:
Debt investments held in a rabbi trust for the Deferred Compensation Plan		[4]		[4]
Fair Value, Inputs, Level 1[Member] | Foreign currency option contracts [Member]
Liabilities:
Foreign currency forward and option contracts		[5]		[5]
Fair Value, Inputs, Level 2 [Member]
Assets:
Total assets	2,245		775
Liabilities:
Total liabilities	729		752
Fair Value, Inputs, Level 2 [Member] | Money market funds and open end mutual funds [Member]
Assets:
Money market funds and open-end mutual funds included in "Cash and cash equivalents"		[1]		[1]
Money market funds and open-end mutual funds in "Deferred charges and other assets"		[1]		[1]
Fair Value, Inputs, Level 2 [Member] | Foreign currency forward contracts [Member]
Assets:
Foreign currency forward and option contracts	2,165	[2]	710	[2]
Fair Value, Inputs, Level 2 [Member] | Equity investments held in a rabbi trust for the Deferred Compensation Plan [Member]
Assets:
Debt investments held in a rabbi trust for the Deferred Compensation Plan		[3]		[3]
Fair Value, Inputs, Level 2 [Member] | Debt investments held in a rabbi trust for the Deferred Compensation Plan [Member]
Assets:
Debt investments held in a rabbi trust for the Deferred Compensation Plan		[3]		[3]
Fair Value, Inputs, Level 2 [Member] | Guaranteed investment certificates [Member]
Assets:
Debt investments held in a rabbi trust for the Deferred Compensation Plan	80	[4]	65	[4]
Fair Value, Inputs, Level 2 [Member] | Foreign currency option contracts [Member]
Liabilities:
Foreign currency forward and option contracts	729	[5]	752	[5]
Fair Value, Inputs, Level 3 [Member]
Assets:
Total assets
Liabilities:
Total liabilities
Fair Value, Inputs, Level 3 [Member] | Money market funds and open end mutual funds [Member]
Assets:
Money market funds and open-end mutual funds included in "Cash and cash equivalents"		[1]		[1]
Money market funds and open-end mutual funds in "Deferred charges and other assets"		[1]		[1]
Fair Value, Inputs, Level 3 [Member] | Foreign currency forward contracts [Member]
Assets:
Foreign currency forward and option contracts		[2]		[2]
Fair Value, Inputs, Level 3 [Member] | Equity investments held in a rabbi trust for the Deferred Compensation Plan [Member]
Assets:
Debt investments held in a rabbi trust for the Deferred Compensation Plan		[3]		[3]
Fair Value, Inputs, Level 3 [Member] | Debt investments held in a rabbi trust for the Deferred Compensation Plan [Member]
Assets:
Debt investments held in a rabbi trust for the Deferred Compensation Plan		[3]		[3]
Fair Value, Inputs, Level 3 [Member] | Guaranteed investment certificates [Member]
Assets:
Debt investments held in a rabbi trust for the Deferred Compensation Plan		[4]		[4]
Fair Value, Inputs, Level 3 [Member] | Foreign currency option contracts [Member]
Liabilities:
Foreign currency forward and option contracts		[5]		[5]

[1] In the accompanying Condensed Consolidated Balance Sheet.

[2] Included in "Other current assets" in the accompanying Condensed Consolidated Balance Sheet. See Note 7.

[3] Included in "Other current assets" in the accompanying Condensed Consolidated Balance Sheet. See Note 8.

[4] Included in "Deferred charges and other assets" in the accompanying Condensed Consolidated Balance Sheet.

[5] Included in "Other accrued expenses and current liabilities" in the accompanying Condensed Consolidated Balance Sheet. See Note 7.