Changes in the accretable yield for the acquired loans in the Westernbank FDIC-assisted transaction (Detail) (Westernbank Puerto Rico [Member], Acquired Loans In An F D I C Assisted Transaction [Member], USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011
Accretable yield
Beginning Balance	$ 1,542,519	$ 1,258,176	$ 1,470,259	$ 1,331,108
Accretion	(73,988)	(100,185)	(143,325)	(173,117)
Reclassifications from nonaccretable balance	0	458,928	0	458,928
Change In Expected Cash Flows	106,319	0	247,916	0
Ending Balance	1,574,850	1,616,919	1,574,850	1,616,919
Carrying amount of loans
Beginning Balance	3,894,905	4,423,496	4,036,471	4,539,928
Accretion	73,988	100,185	143,325	173,117
Collections	(239,404)	(258,616)	(450,307)	(447,980)
Ending Balance	3,729,489	4,265,065	3,729,489	4,265,065
Less: Allowance for loan losses	(93,971)	(48,257)	(93,971)	(48,257)	(83,477)
Carrying amount, net of allowance	3,635,518	4,216,808	3,635,518	4,216,808	3,952,994
Performing Financing Receivable Member
Accretable yield
Beginning Balance	1,514,719	1,244,509	1,428,764	1,307,927
Accretion	(67,982)	(73,457)	(130,449)	(136,875)
Reclassifications from nonaccretable balance	0	375,181	0	375,181
Change In Expected Cash Flows	104,222	0	252,644	0
Ending Balance	1,550,959	1,546,233	1,550,959	1,546,233
Carrying amount of loans
Beginning Balance	3,345,311	3,788,650	3,446,451	3,894,379
Accretion	67,982	73,457	130,449	136,875
Collections	(168,336)	(235,472)	(331,943)	(404,619)
Ending Balance	3,244,957	3,626,635	3,244,957	3,626,635
Less: Allowance for loan losses	(60,370)	(38,633)	(60,370)	(38,633)	(62,951)
Carrying amount, net of allowance	3,184,587	3,588,002	3,184,587	3,588,002	3,383,500
Nonperforming Financing Receivable Member
Accretable yield
Beginning Balance	27,800	13,667	41,495	23,181
Accretion	(6,006)	(26,728)	(12,876)	(36,242)
Reclassifications from nonaccretable balance	0	83,747	0	83,747
Change In Expected Cash Flows	2,097	0	(4,728)	0
Ending Balance	23,891	70,686	23,891	70,686
Carrying amount of loans
Beginning Balance	549,594	634,846	590,020	645,549
Accretion	6,006	26,728	12,876	36,242
Collections	(71,068)	(23,144)	(118,364)	(43,361)
Ending Balance	484,532	638,430	484,532	638,430
Less: Allowance for loan losses	(33,601)	(9,624)	(33,601)	(9,624)	(20,526)
Carrying amount, net of allowance	$ 450,931	$ 628,806	$ 450,931	$ 628,806	$ 569,494