Commitments and Contingencies - Additional Information (Detail) (USD $)				3 Months Ended		6 Months Ended				3 Months Ended		6 Months Ended	3 Months Ended	1 Months Ended
	Jun. 30, 2011	Dec. 31, 2010	Jun. 30, 2010	Sep. 09, 2009 Putative Class Action LegalMatter	Sep. 09, 2009 Derivative Claim LegalMatter	Jun. 30, 2011 Popular, Inc. Holding Co. Hoff v. Popular, Inc., et al Settlement of Litigation	Jun. 30, 2011 Hoff v. Popular, Inc., et al	Jun. 30, 2011 Hoff v. Popular, Inc., et al Settlement of Litigation	Jun. 30, 2011 Hoff v. Popular, Inc., et al Settlement of Litigation Paid by Insurers	Jun. 30, 2011 Garcia and Diaz actions	Jun. 30, 2011 In re Popular, Inc. ERISA Litigation	Jun. 30, 2011 In re Popular, Inc. ERISA Litigation Paid by Insurers	Jun. 30, 2011 Consumer Banking And Trust Related Activities LegalMatter	Dec. 31, 2010 Garcia Lamadrid, et al. v. Banco Popular, et al	Jun. 30, 2011 Covered under Loss Sharing Agreements with FDIC Commitments to Extend Credit Line of Credit	Dec. 31, 2010 Covered under Loss Sharing Agreements with FDIC Commitments to Extend Credit Line of Credit	Jun. 30, 2010 Covered under Loss Sharing Agreements with FDIC Commitments to Extend Credit Line of Credit	Jun. 30, 2011 Commitments to Extend Credit Reserve for Off-balance Sheet Activities Line of Credit	Dec. 31, 2010 Commitments to Extend Credit Reserve for Off-balance Sheet Activities Line of Credit	Jun. 30, 2010 Commitments to Extend Credit Reserve for Off-balance Sheet Activities Line of Credit	Jun. 30, 2011 Commercial real estate Credit Concentration Risk	Dec. 31, 2010 Commercial real estate Credit Concentration Risk	Jun. 30, 2010 Commercial real estate Credit Concentration Risk	Jun. 30, 2011 Credit Concentration Risk Credit facilities granted to or guaranteed by the Puerto Rico Government, its municipalities and public corporation	Dec. 31, 2010 Credit Concentration Risk Credit facilities granted to or guaranteed by the Puerto Rico Government, its municipalities and public corporation	Jun. 30, 2010 Credit Concentration Risk Credit facilities granted to or guaranteed by the Puerto Rico Government, its municipalities and public corporation	Jun. 30, 2011 Credit Concentration Risk Uncommitted Credit Facility	Dec. 31, 2010 Credit Concentration Risk Uncommitted Credit Facility	Jun. 30, 2010 Credit Concentration Risk Uncommitted Credit Facility	Jun. 30, 2011 Credit Concentration Risk Obligations of Puerto Rico, States and political subdivisions	Dec. 31, 2010 Credit Concentration Risk Obligations of Puerto Rico, States and political subdivisions	Jun. 30, 2010 Credit Concentration Risk Obligations of Puerto Rico, States and political subdivisions	Jun. 30, 2011 Banco Popular de Puerto Rico Day	Jun. 30, 2011 Minimum	Jun. 30, 2011 Maximum
Commitments and Contingencies Disclosure [Line Items]
Reserve of potential losses associated with unfunded loan commitments																		$ 11,000,000	$ 21,000,000	$ 34,000,000
Unamortized balance of the contingent liability on unfunded loan commitments															3,000,000	6,000,000	24,000,000
Other non-credit commitments related to the acquisition of other investments	10,000,000	10,000,000	10,000,000
Estimate of possible loss	176,000,000	169,000,000	169,000,000
Business concentration, secured loans and credit facilities																					12,600,000,000	12,000,000,000	13,400,000,000	754,000,000	1,100,000,000	754,000,000
Business concentration, Percentage of real estate-related loans secured by commercial real estate																					61.00%	58.00%	60.00%
Business concentration, credit facilities granted to or guaranteed by the Puerto Rico Government, its municipalities and public corporations																								894,000,000	1,400,000,000	972,000,000	140,000,000	199,000,000	215,000,000
Business concentration, obligations issued or guaranteed by the Puerto Rico Government, its municipalities and public corporations as part of the corporation's investment securities portfolio																														121,000,000	145,000,000	232,000,000
FDIC Loss sharing agreements, days available to make a true-up payment following the "True-Up Measurement Date" (in days)																																	45
Estimate of the aggregate range of reasonably possible losses																																		0	30,000,000
Legal Proceedings, number of claims filed				5	2								2
Estimate of possible loss							37.5
Legal Proceedings, amount paid to the settlement fund						11,500,000		37,500,000	26,000,000
Legal Proceedings, reimbursement by insurers								4,700,000
Subsequent Events Date								Jul. 05, 2011
Legal Proceedings, attorneys' fees and expenses of counsel for the plaintiffs										2,100,000
Legal Proceedings, settlement amount estimated to be covered by insurance										1,600,000
Estimate of possible loss											8,200,000
Legal Proceedings, amount paid to the settlement fund												8,200,000
Legal Proceedings, description of damages sought by plaintiffs														Plaintiffs seek in excess of $600 million in damages, plus costs and attorneys fees.
Legal Proceedings, damages sought by plaintiffs														$ 600,000,000