Reclassification out of accumulated other comprehensive income (loss) (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014		Mar. 31, 2013
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Reclassification adjustment for (gains) losses included in net income (loss)	$ (7,718)	[1]	$ 0	[1]
Personnel costs	113,154		115,989
Noninterest Income Other Operating Income	28,391		20,054
Mortgage banking activities	3,681		20,300
Income Tax Expense Benefit	23,264		(56,877)
Net Income	86,409		(120,307)
Reclassification Out Of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Net Income	(9,549)		(4,211)
Reclassification Out Of Accumulated Other Comprehensive Income [Member] | Accumulated Defined Benefit Plans Adjustment [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest	(1,176)		(6,169)
Income Tax Expense Benefit	458		1,851
Net Income	(718)		(4,318)
Reclassification Out Of Accumulated Other Comprehensive Income [Member] | Accumulated Defined Benefit Plans Adjustment [Member] | Defined Benefit Plan Amortization Of Gains Losses [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Personnel costs	(2,126)		(6,169)
Reclassification Out Of Accumulated Other Comprehensive Income [Member] | Accumulated Defined Benefit Plans Adjustment [Member] | Defined Benefit Plan Amortization Of Prior Service Cost Credit [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Personnel costs	950		0
Reclassification Out Of Accumulated Other Comprehensive Income [Member] | Accumulated Net Gain Loss From Designated Or Qualifying Cash Flow Hedges [Member] | Forward Contracts [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest	(1,824)		152
Mortgage banking activities	(1,824)		152
Income Tax Expense Benefit	711		(45)
Net Income	(1,113)		107
Reclassification Out Of Accumulated Other Comprehensive Income [Member] | Accumulated Translation Adjustment
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest	(7,718)		0
Net Income	$ (7,718)		$ 0

[1] All amounts presented are net of tax.