Condensed Consolidating Statement of Condition (Detail) - USD ($) $ in Thousands		Sep. 30, 2017		Jun. 30, 2017	Dec. 31, 2016		Sep. 30, 2016	Jun. 30, 2016	Dec. 31, 2015
Assets:
Cash And Due From Banks		$ 517,437			$ 362,394
Money market investments		5,488,212			2,890,217
Trading account securities, at fair value		45,951			59,805
Investment securities available-for-sale, at fair value		9,061,001	[1]		8,209,806	[2]
Investment securities held-to-maturity, at amortized cost		93,438	[3]		98,101	[4]
Other investment securities, at lower of cost or realizable value		173,965			167,818
Investment in subsidiaries		0			0
Loans held-for-sale, at lower of cost or fair value		68,864			88,821
Loans held-in-portfolio:
Loans not covered under loss-sharing agreements with the FDIC		23,302,047			22,895,172
Loans covered under loss-sharing agreements with the FDIC		524,854			572,878
Less - Unearned income		128,597			121,425
Allowance for loan losses		646,913		$ 540,014	540,651		$ 555,855	$ 548,720	$ 537,111
Total loans held-in-portfolio, net		23,051,391			22,805,974
FDIC loss-share asset		48,470			69,334
Premises and equipment, net		532,532			543,981
Accrued income receivable		146,339			138,042
Mortgage servicing assets, at fair value		180,157			196,889		200,354		211,405
Other assets		2,329,927			2,145,510
Goodwill		627,294			627,294		627,294		626,388
Other intangible assets		38,016			45,050
Total assets		42,601,267			38,661,609		39,054,296
Deposits:
Non-interest bearing		7,449,857			6,980,443
Interest bearing		26,799,079			23,515,781
Total deposits		34,248,936			30,496,224
Assets sold under agreements to repurchase		374,405			479,425
Other short-term borrowings		240,598			1,200
Notes payable		1,532,061			1,574,852
Other liabilities		919,836			911,951
Total liabilities		37,315,836			33,463,652
Stockholders' equity:
Preferred stock		50,160			50,160
Common stock		1,042			1,040
Surplus		4,265,053			4,255,022
Retained Earnings (Accumulated Deficit)		1,350,730			1,220,307
Treasury stock		(90,222)			(8,286)
Accumulated other comprehensive (loss) income, net of tax	[5]	(291,332)			(320,286)		(157,295)
Total stockholders' equity		5,285,431			5,197,957		$ 5,380,395		$ 5,105,324
Total liabilities and stockholders' equity		42,601,267			38,661,609
Elimination
Assets:
Cash And Due From Banks		(44,620)			(48,081)
Money market investments		(241,038)			(267,063)
Trading account securities, at fair value		(108)			(132)
Investment securities available-for-sale, at fair value		0			0
Investment securities held-to-maturity, at amortized cost		0			0
Other investment securities, at lower of cost or realizable value		0			0
Investment in subsidiaries		(7,498,444)			(7,427,738)
Loans held-for-sale, at lower of cost or fair value		0			0
Loans held-in-portfolio:
Loans not covered under loss-sharing agreements with the FDIC		5,955			0
Loans covered under loss-sharing agreements with the FDIC		0			0
Less - Unearned income		0			0
Allowance for loan losses		0			0
Total loans held-in-portfolio, net		5,955			0
FDIC loss-share asset		0			0
Premises and equipment, net		0			0
Accrued income receivable		(76)			(90)
Mortgage servicing assets, at fair value		0			0
Other assets		(25,874)			(14,968)
Goodwill		0			0
Other intangible assets		0			0
Total assets		(7,804,205)			(7,758,072)
Deposits:
Non-interest bearing		(44,620)			(48,081)
Interest bearing		(241,038)			(267,063)
Total deposits		(285,658)			(315,144)
Assets sold under agreements to repurchase		0			0
Other short-term borrowings		0			0
Notes payable		0			0
Other liabilities		(24,157)			(15,253)
Total liabilities		(309,815)			(330,397)
Stockholders' equity:
Preferred stock		0			0
Common stock		(56,309)			(56,309)
Surplus		(9,792,901)			(9,819,746)
Retained Earnings (Accumulated Deficit)		2,047,315			2,108,578
Treasury stock		(89)			(88)
Accumulated other comprehensive (loss) income, net of tax		307,594			339,890
Total stockholders' equity		(7,494,390)			(7,427,675)
Total liabilities and stockholders' equity		(7,804,205)			(7,758,072)
Non Covered Under Loss Sharing Agreements with FDIC
Loans held-in-portfolio:
Other real estate owned		176,728			180,445
Non Covered Under Loss Sharing Agreements with FDIC | Elimination
Loans held-in-portfolio:
Other real estate owned		0			0
Covered Under Loss Sharing Agreements With FDIC Member
Loans held-in-portfolio:
Loans covered under loss-sharing agreements with the FDIC		524,854	[6]		572,878	[7]
Other real estate owned		21,545			32,128
Covered Under Loss Sharing Agreements With FDIC Member | Elimination
Loans held-in-portfolio:
Other real estate owned		0			0
Popular, Inc. Holding Co.
Assets:
Cash And Due From Banks		44,155			47,783
Money market investments		238,696			252,347
Trading account securities, at fair value		3,600			2,640
Investment securities available-for-sale, at fair value		0			0
Investment securities held-to-maturity, at amortized cost		0			0
Other investment securities, at lower of cost or realizable value		9,850			9,850
Investment in subsidiaries		5,673,204			5,609,611
Loans held-for-sale, at lower of cost or fair value		0			0
Loans held-in-portfolio:
Loans not covered under loss-sharing agreements with the FDIC		32,877			1,142
Loans covered under loss-sharing agreements with the FDIC		0			0
Less - Unearned income		0			0
Allowance for loan losses		311			2
Total loans held-in-portfolio, net		32,566			1,140
FDIC loss-share asset		0			0
Premises and equipment, net		3,174			3,067
Accrued income receivable		227			112
Mortgage servicing assets, at fair value		0			0
Other assets		70,896			61,770
Goodwill		0			0
Other intangible assets		6,114			553
Total assets		6,082,482			5,988,954
Deposits:
Non-interest bearing		0			0
Interest bearing		0			0
Total deposits		0			0
Assets sold under agreements to repurchase		0			0
Other short-term borrowings		0			0
Notes payable		737,163			735,600
Other liabilities		59,799			55,309
Total liabilities		796,962			790,909
Stockholders' equity:
Preferred stock		50,160			50,160
Common stock		1,042			1,040
Surplus		4,256,526			4,246,495
Retained Earnings (Accumulated Deficit)		1,359,257			1,228,834
Treasury stock		(90,133)			(8,198)
Accumulated other comprehensive (loss) income, net of tax		(291,332)			(320,286)
Total stockholders' equity		5,285,520			5,198,045
Total liabilities and stockholders' equity		6,082,482			5,988,954
Popular, Inc. Holding Co. | Non Covered Under Loss Sharing Agreements with FDIC
Loans held-in-portfolio:
Other real estate owned		0			81
Popular, Inc. Holding Co. | Covered Under Loss Sharing Agreements With FDIC Member
Loans held-in-portfolio:
Other real estate owned		0			0
PNA Holding Co.
Assets:
Cash And Due From Banks		462			591
Money market investments		2,771			13,263
Trading account securities, at fair value		0			0
Investment securities available-for-sale, at fair value		0			0
Investment securities held-to-maturity, at amortized cost		0			0
Other investment securities, at lower of cost or realizable value		4,492			4,492
Investment in subsidiaries		1,825,240			1,818,127
Loans held-for-sale, at lower of cost or fair value		0			0
Loans held-in-portfolio:
Loans not covered under loss-sharing agreements with the FDIC		0			0
Loans covered under loss-sharing agreements with the FDIC		0			0
Less - Unearned income		0			0
Allowance for loan losses		0			0
Total loans held-in-portfolio, net		0			0
FDIC loss-share asset		0			0
Premises and equipment, net		0			0
Accrued income receivable		31			138
Mortgage servicing assets, at fair value		0			0
Other assets		28,490			25,146
Goodwill		0			0
Other intangible assets		0			0
Total assets		1,861,486			1,861,757
Deposits:
Non-interest bearing		0			0
Interest bearing		0			0
Total deposits		0			0
Assets sold under agreements to repurchase		0			0
Other short-term borrowings		0			0
Notes payable		148,532			148,512
Other liabilities		2,589			6,034
Total liabilities		151,121			154,546
Stockholders' equity:
Preferred stock		0			0
Common stock		2			2
Surplus		4,100,807			4,111,207
Retained Earnings (Accumulated Deficit)		(2,372,062)			(2,382,049)
Treasury stock		0			0
Accumulated other comprehensive (loss) income, net of tax		(18,382)			(21,949)
Total stockholders' equity		1,710,365			1,707,211
Total liabilities and stockholders' equity		1,861,486			1,861,757
PNA Holding Co. | Non Covered Under Loss Sharing Agreements with FDIC
Loans held-in-portfolio:
Other real estate owned		0			0
PNA Holding Co. | Covered Under Loss Sharing Agreements With FDIC Member
Loans held-in-portfolio:
Other real estate owned		0			0
All other subsidiaries and eliminations
Assets:
Cash And Due From Banks		517,440			362,101
Money market investments		5,487,783			2,891,670
Trading account securities, at fair value		42,459			57,297
Investment securities available-for-sale, at fair value		9,061,001			8,209,806
Investment securities held-to-maturity, at amortized cost		93,438			98,101
Other investment securities, at lower of cost or realizable value		159,623			153,476
Investment in subsidiaries		0			0
Loans held-for-sale, at lower of cost or fair value		68,864			88,821
Loans held-in-portfolio:
Loans not covered under loss-sharing agreements with the FDIC		23,263,215			22,894,030
Loans covered under loss-sharing agreements with the FDIC		524,854			572,878
Less - Unearned income		128,597			121,425
Allowance for loan losses		646,602			540,649
Total loans held-in-portfolio, net		23,012,870			22,804,834
FDIC loss-share asset		48,470			69,334
Premises and equipment, net		529,358			540,914
Accrued income receivable		146,157			137,882
Mortgage servicing assets, at fair value		180,157			196,889
Other assets		2,256,415			2,073,562
Goodwill		627,294			627,294
Other intangible assets		31,902			44,497
Total assets		42,461,504			38,568,970
Deposits:
Non-interest bearing		7,494,477			7,028,524
Interest bearing		27,040,117			23,782,844
Total deposits		34,534,594			30,811,368
Assets sold under agreements to repurchase		374,405			479,425
Other short-term borrowings		240,598			1,200
Notes payable		646,366			690,740
Other liabilities		881,605			865,861
Total liabilities		36,677,568			32,848,594
Stockholders' equity:
Preferred stock		0			0
Common stock		56,307			56,307
Surplus		5,700,621			5,717,066
Retained Earnings (Accumulated Deficit)		316,220			264,944
Treasury stock		0			0
Accumulated other comprehensive (loss) income, net of tax		(289,212)			(317,941)
Total stockholders' equity		5,783,936			5,720,376
Total liabilities and stockholders' equity		42,461,504			38,568,970
All other subsidiaries and eliminations | Non Covered Under Loss Sharing Agreements with FDIC
Loans held-in-portfolio:
Other real estate owned		176,728			180,364
All other subsidiaries and eliminations | Covered Under Loss Sharing Agreements With FDIC Member
Loans held-in-portfolio:
Other real estate owned		$ 21,545			$ 32,128

[1] Includes $6.7 billion pledged to secure public and trust deposits, assets sold under agreements to repurchase, credit facilities and loan servicing agreements that the secured parties are not permitted to sell or repledge the collateral, of which $5.7 billion serve as collateral for public funds.

[2] Includes $4.1 billion pledged to secure public and trust deposits, assets sold under agreements to repurchase, credit facilities and loan servicing agreements that the secured parties are not permitted to sell or repledge the collateral, of which $3.4 billion serve as collateral for public funds.

[3] Includes $92.4 million pledged to secure public and trust deposits that the secured parties are not permitted to sell or repledge the collateral.

[4] Includes $53.1 million pledged to secure public and trust deposits that the secured parties are not permitted to sell or repledge the collateral.

[5] All amounts presented are net of tax.

[6] Includes $296 million pledged to secure credit facilities at the FHLB which are not permitted to sell or repledge the collateral.

[7] Includes $337 million pledged to secure credit facilities at the FHLB which are not permitted to sell or repledge the collateral.