Carrying or notional amounts and estimated fair values for financial instruments (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014		Dec. 31, 2013		Jun. 30, 2013	Dec. 31, 2012
Assets, Fair Value Disclosure [Abstract]
Cash And Due From Banks	$ 362,572		$ 423,211		$ 388,041	$ 439,363
Money market investments	1,666,944		858,453
Trading account securities, at fair value	345,823		339,743
Available For Sale Securities	5,653,992		5,294,800
Held To Maturity Securities Fair Value	103,501		120,688
Marketable Securities, Alternative [Abstract]
Servicing Asset At Fair Value Amount	151,951		161,099		153,444	154,430
Derivative Asset, Fair Value, Gross Asset	27,559		34,710
Deposits, by Type [Abstract]
Time Deposits	7,668,773		8,311,352
Federal Funds Purchased and Securities Sold under Agreements to Repurchase [Abstract]
Federal Funds Purchased	250,000		0
Securities Sold under Agreements to Repurchase	1,824,676		1,659,292
Notes Payable [Abstract]
Other Notes Payable	23,093		23,496
Fixed Rate 6125 To 8327 Percent Junior Subordinated Deferrable Interest Debentures Due 2027 To 2034 [Member]
Notes Payable [Abstract]
Junior Subordinated Debenture Owed To Unconsolidated Subsidiary Trust	439,800		439,800
Fixed Rate 500 Percent Until December 2013 And 900 Percent Thereafter Junior Subordinated Deferrable Interest Debentures With No Stated Maturity [Member]
Notes Payable [Abstract]
Junior Subordinated Debenture Owed To Unconsolidated Subsidiary Trust	936,000	[1]	531,540	[1]
Fixed Rate 700 Percent Notes Due July 2019 [Member]
Notes Payable [Abstract]
Senior Long Term Notes	450,000		0
Puerto Rico States And Political Subdivisions Debt Securities [Member]
Assets, Fair Value Disclosure [Abstract]
Available For Sale Securities	69,171		66,377
Held To Maturity Securities Fair Value	101,906		94,712
Collateralized Mortgage Obligations Issued By Private Enterprise [Member]
Assets, Fair Value Disclosure [Abstract]
Available For Sale Securities	130		513
Held To Maturity Securities Fair Value	0		0
Collateralized Mortgage Obligations Issued By U S Government Sponsored Enterprises And U S Government [Member]
Assets, Fair Value Disclosure [Abstract]
Available For Sale Securities	2,303,472		2,418,296
Held To Maturity Securities Fair Value	96		122
Other Securities [Member]
Assets, Fair Value Disclosure [Abstract]
Available For Sale Securities	11,869		12,170
Held To Maturity Securities Fair Value	1,499		25,854
Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Cash And Due From Banks	362,572		423,211
Money market investments	1,474,592		677,033
Trading account securities, at fair value	0	[2]	0	[2]
Available For Sale Securities	213	[2]	412	[2]
Held To Maturity Securities Fair Value	0		0
Marketable Securities, Alternative [Abstract]
Federal Home Loan Bank Stock	0		0
Federal Reserve Bank Stock	0		0
Trust Preferred Securities	0		0
Other Investments	0		0
Total other investment securities	0		0
Loans held-for-sale	0		0
FDIC loss share asset	0		0
Servicing Asset At Fair Value Amount	0		0
Derivative Asset, Fair Value, Gross Asset	0		0
Deposits, by Type [Abstract]
Demand Deposit Accounts	0		0
Time Deposits	0		0
Deposits	0		0
Federal Funds Purchased and Securities Sold under Agreements to Repurchase [Abstract]
Securities Sold under Agreements to Repurchase	0		0
Assets sold under agreements to repurchase	0		0
Other short-term borrowings	0	[3]	0	[3]
Notes Payable [Abstract]
Federal Home Loan Bank Advances Long Term	0		0
Medium-term Notes	0		0
Other Notes Payable	0		0
Notes payable	0		0
Derivative Financial Instruments Liabilities Fair Value Disclosure	0		0
Business Combination Contingent Consideration Liability	0		0
Fair Value Off Balance Sheet [Abstract]
Commitments to extend credit	0		0
Letters of credit Fair Value Disclosure	0		0
Fair Value, Inputs, Level 1 [Member] | Structured Finance [Member]
Federal Funds Purchased and Securities Sold under Agreements to Repurchase [Abstract]
Securities Sold under Agreements to Repurchase	0		0
Fair Value, Inputs, Level 1 [Member] | Fixed Rate 6125 To 8327 Percent Junior Subordinated Deferrable Interest Debentures Due 2027 To 2034 [Member]
Notes Payable [Abstract]
Junior Subordinated Debenture Owed To Unconsolidated Subsidiary Trust	0		0
Fair Value, Inputs, Level 1 [Member] | Fixed Rate 500 Percent Until December 2013 And 900 Percent Thereafter Junior Subordinated Deferrable Interest Debentures With No Stated Maturity [Member]
Notes Payable [Abstract]
Junior Subordinated Debenture Owed To Unconsolidated Subsidiary Trust	0		0
Fair Value, Inputs, Level 1 [Member] | Puerto Rico States And Political Subdivisions Debt Securities [Member]
Assets, Fair Value Disclosure [Abstract]
Held To Maturity Securities Fair Value	0		0
Fair Value, Inputs, Level 1 [Member] | Collateralized Mortgage Obligations Issued By U S Government Sponsored Enterprises And U S Government [Member]
Assets, Fair Value Disclosure [Abstract]
Held To Maturity Securities Fair Value	0		0
Fair Value, Inputs, Level 1 [Member] | Other Securities [Member]
Assets, Fair Value Disclosure [Abstract]
Held To Maturity Securities Fair Value	0		0
Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Cash And Due From Banks	0		0
Money market investments	192,352		181,420
Trading account securities, at fair value	335,217	[2]	326,509	[2]
Available For Sale Securities	5,647,610	[2]	5,287,865	[2]
Held To Maturity Securities Fair Value	1,499		1,500
Marketable Securities, Alternative [Abstract]
Federal Home Loan Bank Stock	64,021		85,245
Federal Reserve Bank Stock	87,981		80,385
Trust Preferred Securities	13,197		13,197
Other Investments	0		0
Total other investment securities	165,199		178,827
Loans held-for-sale	5,361		3,155
FDIC loss share asset	0		0
Servicing Asset At Fair Value Amount	0		0
Derivative Asset, Fair Value, Gross Asset	27,586		34,793
Deposits, by Type [Abstract]
Demand Deposit Accounts	17,232,379		18,399,793
Time Deposits	7,709,103		8,367,410
Deposits	24,941,482		26,767,203
Federal Funds Purchased and Securities Sold under Agreements to Repurchase [Abstract]
Securities Sold under Agreements to Repurchase	1,411,777		1,025,628
Assets sold under agreements to repurchase	2,126,674		1,720,050
Other short-term borrowings	31,200	[3]	401,200	[3]
Notes Payable [Abstract]
Federal Home Loan Bank Advances Long Term	526,054		604,976
Medium-term Notes	0		0
Other Notes Payable	0		0
Notes payable	1,355,129		953,198
Derivative Financial Instruments Liabilities Fair Value Disclosure	25,611		32,378
Business Combination Contingent Consideration Liability	0		0
Fair Value Off Balance Sheet [Abstract]
Commitments to extend credit	0		0
Letters of credit Fair Value Disclosure	0		0
Fair Value, Inputs, Level 2 [Member] | Structured Finance [Member]
Federal Funds Purchased and Securities Sold under Agreements to Repurchase [Abstract]
Securities Sold under Agreements to Repurchase	714,897		694,422
Fair Value, Inputs, Level 2 [Member] | Fixed Rate 6125 To 8327 Percent Junior Subordinated Deferrable Interest Debentures Due 2027 To 2034 [Member]
Notes Payable [Abstract]
Junior Subordinated Debenture Owed To Unconsolidated Subsidiary Trust	371,762		348,222
Fair Value, Inputs, Level 2 [Member] | Fixed Rate 500 Percent Until December 2013 And 900 Percent Thereafter Junior Subordinated Deferrable Interest Debentures With No Stated Maturity [Member]
Notes Payable [Abstract]
Junior Subordinated Debenture Owed To Unconsolidated Subsidiary Trust	0		0
Fair Value, Inputs, Level 2 [Member] | Puerto Rico States And Political Subdivisions Debt Securities [Member]
Assets, Fair Value Disclosure [Abstract]
Held To Maturity Securities Fair Value	0		0
Fair Value, Inputs, Level 2 [Member] | Collateralized Mortgage Obligations Issued By U S Government Sponsored Enterprises And U S Government [Member]
Assets, Fair Value Disclosure [Abstract]
Held To Maturity Securities Fair Value	0		0
Fair Value, Inputs, Level 2 [Member] | Other Securities [Member]
Assets, Fair Value Disclosure [Abstract]
Held To Maturity Securities Fair Value	1,499		1,500
Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Cash And Due From Banks	0		0
Money market investments	0		0
Trading account securities, at fair value	10,579	[2]	13,151	[2]
Available For Sale Securities	6,169	[2]	6,523	[2]
Held To Maturity Securities Fair Value	102,002		119,188
Marketable Securities, Alternative [Abstract]
Federal Home Loan Bank Stock	0		0
Federal Reserve Bank Stock	0		0
Trust Preferred Securities	1,000		1,000
Other Investments	4,501		4,699
Total other investment securities	5,501		5,699
Loans held-for-sale	94,765		109,405
FDIC loss share asset	627,360		837,131
Servicing Asset At Fair Value Amount	151,951		161,099
Derivative Asset, Fair Value, Gross Asset	0		0
Deposits, by Type [Abstract]
Demand Deposit Accounts	0		0
Time Deposits	0		0
Deposits	0		0
Federal Funds Purchased and Securities Sold under Agreements to Repurchase [Abstract]
Securities Sold under Agreements to Repurchase	0		0
Assets sold under agreements to repurchase	0		0
Other short-term borrowings	0	[3]	0	[3]
Notes Payable [Abstract]
Federal Home Loan Bank Advances Long Term	0		0
Medium-term Notes	707		716
Other Notes Payable	23,093		23,496
Notes payable	959,800		1,030,850
Derivative Financial Instruments Liabilities Fair Value Disclosure	0		0
Business Combination Contingent Consideration Liability	127,551		128,299
Fair Value Off Balance Sheet [Abstract]
Commitments to extend credit	1,983		2,571
Letters of credit Fair Value Disclosure	837		901
Fair Value, Inputs, Level 3 [Member] | Structured Finance [Member]
Federal Funds Purchased and Securities Sold under Agreements to Repurchase [Abstract]
Securities Sold under Agreements to Repurchase	0		0
Fair Value, Inputs, Level 3 [Member] | Fixed Rate 6125 To 8327 Percent Junior Subordinated Deferrable Interest Debentures Due 2027 To 2034 [Member]
Notes Payable [Abstract]
Junior Subordinated Debenture Owed To Unconsolidated Subsidiary Trust	0		0
Fair Value, Inputs, Level 3 [Member] | Fixed Rate 500 Percent Until December 2013 And 900 Percent Thereafter Junior Subordinated Deferrable Interest Debentures With No Stated Maturity [Member]
Notes Payable [Abstract]
Junior Subordinated Debenture Owed To Unconsolidated Subsidiary Trust	936,000		1,006,638
Fair Value, Inputs, Level 3 [Member] | Puerto Rico States And Political Subdivisions Debt Securities [Member]
Assets, Fair Value Disclosure [Abstract]
Held To Maturity Securities Fair Value	101,906		94,712
Fair Value, Inputs, Level 3 [Member] | Collateralized Mortgage Obligations Issued By U S Government Sponsored Enterprises And U S Government [Member]
Assets, Fair Value Disclosure [Abstract]
Held To Maturity Securities Fair Value	96		122
Fair Value, Inputs, Level 3 [Member] | Other Securities [Member]
Assets, Fair Value Disclosure [Abstract]
Held To Maturity Securities Fair Value	0		24,354
Non Covered Under Loss Sharing Agreements With F D I C [Member] | Fair Value, Inputs, Level 1 [Member]
Marketable Securities, Alternative [Abstract]
Loans held-in-portfolio, net	0		0
Non Covered Under Loss Sharing Agreements With F D I C [Member] | Fair Value, Inputs, Level 2 [Member]
Marketable Securities, Alternative [Abstract]
Loans held-in-portfolio, net	0		0
Non Covered Under Loss Sharing Agreements With F D I C [Member] | Fair Value, Inputs, Level 3 [Member]
Marketable Securities, Alternative [Abstract]
Loans held-in-portfolio, net	17,879,517		19,070,337
Covered Under Loss Sharing Agreements With F D I C [Member] | Fair Value, Inputs, Level 1 [Member]
Marketable Securities, Alternative [Abstract]
Loans held-in-portfolio, net	0		0
Covered Under Loss Sharing Agreements With F D I C [Member] | Fair Value, Inputs, Level 2 [Member]
Marketable Securities, Alternative [Abstract]
Loans held-in-portfolio, net	0		0
Covered Under Loss Sharing Agreements With F D I C [Member] | Fair Value, Inputs, Level 3 [Member]
Marketable Securities, Alternative [Abstract]
Loans held-in-portfolio, net	3,127,324		3,404,128
Carrying (Reported) Amount, Fair Value Disclosure
Assets, Fair Value Disclosure [Abstract]
Cash And Due From Banks	362,572		423,211
Money market investments	1,666,944		858,453
Trading account securities, at fair value	345,796	[2]	339,660	[2]
Available For Sale Securities	5,653,992	[2]	5,294,800	[2]
Held To Maturity Securities Fair Value	114,280		140,496
Marketable Securities, Alternative [Abstract]
Federal Home Loan Bank Stock	64,021		85,245
Federal Reserve Bank Stock	87,981		80,385
Trust Preferred Securities	14,197		14,197
Other Investments	1,926		1,925
Total other investment securities	168,125		181,752
Loans held-for-sale	97,010		110,426
FDIC loss share asset	751,553		948,608
Servicing Asset At Fair Value Amount	151,951		161,099
Derivative Asset, Fair Value, Gross Asset	27,586		34,793
Deposits, by Type [Abstract]
Demand Deposit Accounts	17,232,379		18,399,793
Time Deposits	7,668,773		8,311,352
Deposits	24,901,152		26,711,145
Federal Funds Purchased and Securities Sold under Agreements to Repurchase [Abstract]
Securities Sold under Agreements to Repurchase	1,407,771		1,021,102
Assets sold under agreements to repurchase	2,074,676		1,659,292
Other short-term borrowings	31,200	[3]	401,200	[3]
Notes Payable [Abstract]
Federal Home Loan Bank Advances Long Term	510,514		589,229
Medium-term Notes	682		689
Senior Long Term Notes	450,000
Other Notes Payable	23,093		23,496
Notes payable	2,360,089		1,584,754
Derivative Financial Instruments Liabilities Fair Value Disclosure	25,611		32,378
Business Combination Contingent Consideration Liability	127,551		128,299
Carrying (Reported) Amount, Fair Value Disclosure | Structured Finance [Member]
Federal Funds Purchased and Securities Sold under Agreements to Repurchase [Abstract]
Securities Sold under Agreements to Repurchase	666,905		638,190
Carrying (Reported) Amount, Fair Value Disclosure | Fixed Rate 6125 To 8327 Percent Junior Subordinated Deferrable Interest Debentures Due 2027 To 2034 [Member]
Notes Payable [Abstract]
Junior Subordinated Debenture Owed To Unconsolidated Subsidiary Trust	439,800		439,800
Carrying (Reported) Amount, Fair Value Disclosure | Fixed Rate 500 Percent Until December 2013 And 900 Percent Thereafter Junior Subordinated Deferrable Interest Debentures With No Stated Maturity [Member]
Notes Payable [Abstract]
Junior Subordinated Debenture Owed To Unconsolidated Subsidiary Trust	936,000		531,540
Carrying (Reported) Amount, Fair Value Disclosure | Puerto Rico States And Political Subdivisions Debt Securities [Member]
Assets, Fair Value Disclosure [Abstract]
Held To Maturity Securities Fair Value	112,676		113,881
Carrying (Reported) Amount, Fair Value Disclosure | Collateralized Mortgage Obligations Issued By U S Government Sponsored Enterprises And U S Government [Member]
Assets, Fair Value Disclosure [Abstract]
Held To Maturity Securities Fair Value	104		115
Carrying (Reported) Amount, Fair Value Disclosure | Other Securities [Member]
Assets, Fair Value Disclosure [Abstract]
Held To Maturity Securities Fair Value	1,500		26,500
Carrying (Reported) Amount, Fair Value Disclosure | Non Covered Under Loss Sharing Agreements With F D I C [Member]
Marketable Securities, Alternative [Abstract]
Loans held-in-portfolio, net	19,108,978		21,073,403
Carrying (Reported) Amount, Fair Value Disclosure | Covered Under Loss Sharing Agreements With F D I C [Member]
Marketable Securities, Alternative [Abstract]
Loans held-in-portfolio, net	2,637,437		2,882,335
Estimate of Fair Value, Fair Value Disclosure
Assets, Fair Value Disclosure [Abstract]
Cash And Due From Banks	362,572		423,211
Money market investments	1,666,944		858,453
Trading account securities, at fair value	345,796	[2]	339,660	[2]
Available For Sale Securities	5,653,992	[2]	5,294,800	[2]
Held To Maturity Securities Fair Value	103,501		120,688
Marketable Securities, Alternative [Abstract]
Federal Home Loan Bank Stock	64,021		85,245
Federal Reserve Bank Stock	87,981		80,385
Trust Preferred Securities	14,197		14,197
Other Investments	4,501		4,699
Total other investment securities	170,700		184,526
Loans held-for-sale	100,126		112,560
FDIC loss share asset	627,360		837,131
Servicing Asset At Fair Value Amount	151,951		161,099
Derivative Asset, Fair Value, Gross Asset	27,586		34,793
Deposits, by Type [Abstract]
Demand Deposit Accounts	17,232,379		18,399,793
Time Deposits	7,709,103		8,367,410
Deposits	24,941,482		26,767,203
Federal Funds Purchased and Securities Sold under Agreements to Repurchase [Abstract]
Securities Sold under Agreements to Repurchase	1,411,777		1,025,628
Assets sold under agreements to repurchase	2,126,674		1,720,050
Other short-term borrowings	31,200	[3]	401,200	[3]
Notes Payable [Abstract]
Federal Home Loan Bank Advances Long Term	526,054		604,976
Medium-term Notes	707		716
Senior Long Term Notes	457,313
Other Notes Payable	23,093		23,496
Notes payable	2,314,929		1,984,048
Derivative Financial Instruments Liabilities Fair Value Disclosure	25,611		32,378
Business Combination Contingent Consideration Liability	127,551		128,299
Fair Value Off Balance Sheet [Abstract]
Commitments to extend credit	1,983		2,571
Letters of credit Fair Value Disclosure	837		901
Estimate of Fair Value, Fair Value Disclosure | Structured Finance [Member]
Federal Funds Purchased and Securities Sold under Agreements to Repurchase [Abstract]
Securities Sold under Agreements to Repurchase	714,897		694,422
Estimate of Fair Value, Fair Value Disclosure | Fixed Rate 6125 To 8327 Percent Junior Subordinated Deferrable Interest Debentures Due 2027 To 2034 [Member]
Notes Payable [Abstract]
Junior Subordinated Debenture Owed To Unconsolidated Subsidiary Trust	371,762		348,222
Estimate of Fair Value, Fair Value Disclosure | Fixed Rate 500 Percent Until December 2013 And 900 Percent Thereafter Junior Subordinated Deferrable Interest Debentures With No Stated Maturity [Member]
Notes Payable [Abstract]
Junior Subordinated Debenture Owed To Unconsolidated Subsidiary Trust	936,000		1,006,638
Estimate of Fair Value, Fair Value Disclosure | Puerto Rico States And Political Subdivisions Debt Securities [Member]
Assets, Fair Value Disclosure [Abstract]
Held To Maturity Securities Fair Value	101,906		94,712
Estimate of Fair Value, Fair Value Disclosure | Collateralized Mortgage Obligations Issued By U S Government Sponsored Enterprises And U S Government [Member]
Assets, Fair Value Disclosure [Abstract]
Held To Maturity Securities Fair Value	96		122
Estimate of Fair Value, Fair Value Disclosure | Other Securities [Member]
Assets, Fair Value Disclosure [Abstract]
Held To Maturity Securities Fair Value	1,499		25,854
Estimate of Fair Value, Fair Value Disclosure | Fair Value, Inputs, Level 1 [Member]
Notes Payable [Abstract]
Senior Long Term Notes	0
Estimate of Fair Value, Fair Value Disclosure | Fair Value, Inputs, Level 2 [Member]
Notes Payable [Abstract]
Senior Long Term Notes	457,313
Estimate of Fair Value, Fair Value Disclosure | Fair Value, Inputs, Level 3 [Member]
Notes Payable [Abstract]
Senior Long Term Notes	0
Estimate of Fair Value, Fair Value Disclosure | Non Covered Under Loss Sharing Agreements With F D I C [Member]
Marketable Securities, Alternative [Abstract]
Loans held-in-portfolio, net	17,879,517		19,070,337
Estimate of Fair Value, Fair Value Disclosure | Covered Under Loss Sharing Agreements With F D I C [Member]
Marketable Securities, Alternative [Abstract]
Loans held-in-portfolio, net	3,127,324		3,404,128
Notional Amount [Member]
Fair Value Off Balance Sheet [Abstract]
Commitments to extend credit	6,941,925		7,490,927
Letters of credit Fair Value Disclosure	$ 52,383		$ 82,007

[1] The debentures are perpetual and may be redeemed by the Corporation at any time, subject to the consent of the Board of Governors of the Federal Reserve System. The discount on the debentures was being amortized over an estimated 30-year term that started in August 2009. During the quarter ended June 30, 2014, in connection with the repayment of these Notes completed on July 2, 2014, the Corporation accelerated the related amortization of the discount and deferred costs amounting to $414.1 million, which is reflected as interest expense in the consolidated statement of operations. The effective interest rate, including the discount accretion, was approximately 16% at December 31, 2013.

[2] Refer to Note 27 to the consolidated financial statements for the fair value by class of financial asset and its hierarchy level.

[3] Refer to Note 18 to the consolidated financial statements for the composition of short-term borrowings.