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, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Accretable yield
Beginning Balance	$ 1,372,135	$ 1,542,519	$ 1,451,669	$ 1,470,259
Accretion	(62,536)	(73,988)	(127,526)	(143,325)
Change In Expected Cash Flows	70,013	106,319	55,469	247,916
Ending Balance	1,379,612	1,574,850	1,379,612	1,574,850
Carrying amount of loans
Beginning Balance	3,157,663	3,894,905	3,491,759	4,036,471
Accretion	62,536	73,988	127,526	143,325
Collections	(207,333)	(239,404)	(606,419)	(450,307)
Ending Balance	3,012,866	3,729,489	3,012,866	3,729,489
Less: Allowance for loan losses	(91,195)	(93,971)	(91,195)	(93,971)	(95,407)
Carrying amount, net of allowance	2,921,671	3,635,518	2,921,671	3,635,518	3,396,352
Performing Financing Receivable Member
Accretable yield
Beginning Balance	1,372,375	1,514,719	1,446,381	1,428,764
Accretion	(60,284)	(67,982)	(121,461)	(130,449)
Change In Expected Cash Flows	53,579	104,222	40,750	252,644
Ending Balance	1,365,670	1,550,959	1,365,670	1,550,959
Carrying amount of loans
Beginning Balance	2,758,944	3,345,311	3,051,964	3,446,451
Accretion	60,284	67,982	121,461	130,449
Collections	(166,157)	(168,336)	(520,354)	(331,943)
Ending Balance	2,653,071	3,244,957	2,653,071	3,244,957
Less: Allowance for loan losses	(47,017)	(60,370)	(47,017)	(60,370)	(48,365)
Carrying amount, net of allowance	2,606,054	3,184,587	2,606,054	3,184,587	3,003,599
Nonperforming Financing Receivable Member
Accretable yield
Beginning Balance	(240)	27,800	5,288	41,495
Accretion	(2,252)	(6,006)	(6,065)	(12,876)
Change In Expected Cash Flows	16,434	2,097	14,719	(4,728)
Ending Balance	13,942	23,891	13,942	23,891
Carrying amount of loans
Beginning Balance	398,719	549,594	439,795	590,020
Accretion	2,252	6,006	6,065	12,876
Collections	(41,176)	(71,068)	(86,065)	(118,364)
Ending Balance	359,795	484,532	359,795	484,532
Less: Allowance for loan losses	(44,178)	(33,601)	(44,178)	(33,601)	(47,042)
Carrying amount, net of allowance	$ 315,617	$ 450,931	$ 315,617	$ 450,931	$ 392,753