Differences between income tax expense (benefit) applicable to income before income taxes and amount computed by applying the statutory tax rate in Puerto Rico (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Income Tax Expense Benefit Continuing Operations Income Tax Reconciliation Abstract
Income tax (benefit) expense	$ 16,192	$ 147,227
PUERTO RICO
Income Tax Expense Benefit Continuing Operations Income Tax Reconciliation Abstract
Computed income tax at statutory rates	19,380	47,207
Net benefit of net tax exempt interest income	(7,014)	(2,407)
Deferred tax asset valuation allowance	1,167	(5,305)
Non-deductible expenses	5,639	5,326
Difference in tax rates due to multiple jurisdictions	(3,207)	(2,464)
Adjustment for enacted changes in income tax laws	0	103,287
Income Tax Reconciliation Other Adjustments	1,198	1,815
Income tax (benefit) expense	16,192	147,227
Effective Income Tax Rate Continuing Operations Tax Rate Reconciliation Abstract
Computed income tax at statutory rates	30.00%	30.00%
Effective Income Tax Rate Reconciliation Tax Exempt Income	(11.00%)	(2.00%)
Deferred tax asset valuation allowance	2.00%	(3.00%)
Non-deductible expenses	9.00%	3.00%
Difference in tax rates due to multiple jurisdictions	(5.00%)	(2.00%)
Effective Income Tax Rate Reconciliation Change In Enacted Tax Rate	0.00%	66.00%
Effective Income Tax Rate Reconciliation Prior Year Income Taxes	0.00%	0.00%
Income tax (benefit) expense	25.00%	93.00%
PUERTO RICO | Effect Of Income Subject To Preferential Tax Rate [Member]
Income Tax Expense Benefit Continuing Operations Income Tax Reconciliation Abstract
Income tax reconciliation, other deductions	(971)	(232)
Effective Income Tax Rate Continuing Operations Tax Rate Reconciliation Abstract
Effective Income Tax Rate Reconciliation Deductions Other	(2.00%)
PUERTO RICO | Recognition Of Tax Benefits From Previous Years [Member]
Income Tax Expense Benefit Continuing Operations Income Tax Reconciliation Abstract
Income tax reconciliation, other deductions	$ 0	$ 0
PUERTO RICO | State Taxes And Others [Member]
Effective Income Tax Rate Continuing Operations Tax Rate Reconciliation Abstract
Effective Income Tax Rate Reconciliation Deductions Other	2.00%	1.00%