Investments held-to-maturity-Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	$ 140,355	$ 142,817
Puerto Rico States And Political Subdivisions Debt Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	113,733	116,177
Puerto Rico States And Political Subdivisions Debt Securities [Member] \| Munis Payable From Real and Personal Property Taxes [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	64,000
Puerto Rico States And Political Subdivisions Debt Securities [Member] \| Munis Guaranteed By Puerto Rico Central Government [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	$ 40,000

For an unclassified balance sheet, this item represents investments in debt securities which are categorized as held-to-maturity. The held-to-maturity category is for those securities that the entity has the positive intent and ability to hold until maturity.

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

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Reference 5: http://www.xbrl.org/2003/role/presentationRef

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Reference 6: http://www.xbrl.org/2003/role/presentationRef

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Reference 8: http://www.xbrl.org/2003/role/presentationRef

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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