Activity and Balances for Restructuring and Asset Impairment (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010
Restructuring Cost and Reserve [Line Items]
Restructuring Liability beginning of period	$ 7,964	$ 8,942
Initial Restructuring Charges	421	36
Subsequent Plan Adjustments	1,658	1,400
Cash Payments	(2,450)	(2,414)
Restructuring Liability end of period	7,593	7,964
Activity for 2011 restructuring charge | Real estate obligations
Restructuring Cost and Reserve [Line Items]
Initial Restructuring Charges	421
Subsequent Plan Adjustments	60
Cash Payments	(120)
Restructuring Liability end of period	361
Activity for 2010 restructuring charge | Real estate obligations
Restructuring Cost and Reserve [Line Items]
Restructuring Liability beginning of period	12
Initial Restructuring Charges		36
Subsequent Plan Adjustments		(5)
Cash Payments	(12)	(19)
Restructuring Liability end of period		12
Activity for 2007 restructuring charge | Real estate obligations
Restructuring Cost and Reserve [Line Items]
Restructuring Liability beginning of period	5,635	6,248
Subsequent Plan Adjustments	1,124	938
Cash Payments	(1,597)	(1,551)
Restructuring Liability end of period	5,162	5,635
Activity for 2001 restructuring charge | Real estate obligations
Restructuring Cost and Reserve [Line Items]
Restructuring Liability beginning of period	2,317	2,480
Subsequent Plan Adjustments	474	438
Cash Payments	(721)	(601)
Restructuring Liability end of period	2,070	2,317
Restructuring - Fiscal 2009 Plan | Real estate obligations
Restructuring Cost and Reserve [Line Items]
Restructuring Liability beginning of period		178
Subsequent Plan Adjustments		11
Cash Payments		(189)
Restructuring - Fiscal 2009 Plan | Employee terminations
Restructuring Cost and Reserve [Line Items]
Restructuring Liability beginning of period		36
Subsequent Plan Adjustments		18
Cash Payments		$ (54)