Disclosure of accumulated other comprehensive loss (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Foreign currency translation adjustment	$ (29,895)	$ (28,829)
Pension and postretirement benefit plans	(314,569)	(333,287)
Tax effect	112,054	117,229
Net of tax amount	(202,515)	(216,058)
Unrealized holding gains on securities available-for-sale	198,009	230,746
Tax effect	(22,240)	(27,668)
Net of tax amount	175,769	203,078
Accumulated Other Comprehensive Income Loss Cumulative Changes In Net Gain Loss From Cash Flow Hedges Effect Pretax	(3,992)	(1,057)
Tax effect	1,198	318
Net of tax amount	(2,794)	(739)
Accumulated other comprehensive income (loss)	$ (59,435)	$ (42,548)