Condensed Consolidating Statement of Cash Flow (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Cash flows from operating activities:
Net Income	$ 20,664	$ 46,810	$ 209,835	$ 220,796
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Equity in losses (earnings) of subsidiaries, net of dividends or distributions			0	0
Provision (reversal) for loan losses			253,936	128,651
Goodwill impairment charge	0	3,801	0	3,801
Amortization of intangibles			7,034	9,308
Depreciation and amortization of premises and equipment			35,966	34,725
Net accretion of discounts and amortization of premiums and deferred fees			(17,371)	(36,753)
Impairment losses on long-lived assets			11,286	0
Other-than-temporary impairment on investment securities	0	0	8,299	209
Fair value adjustments on mortgage servicing rights			24,262	18,879
FDIC loss share (income) expense			12,680	77,445
Adjustments (expense) to indemnity reserves on loans sold	6,406	4,390	11,302	14,234
Earnings from investments under the equity method			(27,350)	(23,812)
Deferred income tax (benefit) expense			30,471	61,918
(Gain) loss on:
Disposition of premises and equipment and other productive assets			5,018	3,603
Sale and valuation adjustments of investment securities			(284)	(1,932)
Sale of loans, including valuation adjustments on loans held-for-sale and mortgage banking activities			(16,455)	(32,982)
Sale of foreclosed assets, including write-downs			19,228	13,160
Acquisitions of loans held-for-sale			(204,813)	(223,189)
Proceeds from sale of loans held-for-sale			68,326	58,003
Net originations on loans held-for-sale			(283,709)	(365,353)
Net (increase) decrease in:
Trading securities			498,840	578,133
Accrued income receivable			(8,297)	4,543
Other assets			13,454	(28,201)
Net increase (decrease) in:
Interest payable			(9,299)	(11,553)
Pension and other postretirement benefits obligation			(13,760)	(56,537)
Other liabilities			15,178	(5,292)
Total adjustments			433,942	221,008
Net Cash Provided By Used In Operating Activities			643,777	441,804
Cash flows from investing activities:
Net (increase) decrease in money market investments			(2,597,994)	(1,783,402)
Purchases of investment securities:
Available-for-sale			(2,356,389)	(2,408,514)
Other			(23,822)	(14,017)
Proceeds from calls, paydowns, maturities and redemptions of investment securities:
Available-for-sale			1,225,915	951,447
Held-to-maturity			6,229	4,182
Other			0	11,051
Proceeds from the sale of investment securities available-for-sale			14,888	1,556
Proceeds from sale of other investment securities			17,675	8,006
Net repayments on loans			(77,400)	(93,354)
Proceeds from sale of loans			415	134,114
Acquisition of loan portfolios			(448,121)	(355,507)
Acquisition of trademark			0
Net payments from FDIC under loss sharing agreements			(11,520)	95,407
Return of capital from equity method investments			8,556	324
Capital Contribution Subsidiaries			0
Return Of Capital From Wholly Owned Subsidiaries			0	0
Acquisition of premises and equipment			(40,158)	(78,297)
Proceeds from sale of:
Premises and equipment and other productive assets			6,982	5,519
Foreclosed assets			85,705	54,600
Net cash (used in) provided by investing activities			(4,189,039)	(3,466,885)
Net increase (decrease) in:
Deposits			3,751,367	3,119,674
Federal funds purchased and assets sold under agreements to repurchase			(105,020)	3,106
Other short-term borrowings			239,398	0
Payments of notes payable			(89,375)	(230,608)
Proceeds from issuance of notes payable			45,000	165,047
Proceeds from issuance of common stock			5,515	5,718
Cash Dividends Paid To Parent Company			0	0
Dividends paid			(69,162)	(49,438)
Net payments for repurchase of common stock			(75,662)	(1,547)
Return Of Capital To Parent Company			0
Capital contribution from parent			0
Payments related to tax witholding for shared-based compensation			(1,756)	0
Net cash (used in) provided by financing activities			3,700,305	3,011,952
Net (decrease) increase in cash and due from banks			155,043	(13,129)
Cash and due from banks at beginning of period			362,394	363,674	$ 363,674
Cash and due from banks at end of period	517,437	350,545	517,437	350,545	362,394
Elimination
Cash flows from operating activities:
Net Income	(21,767)	(60,359)	(245,264)	(273,087)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Equity in losses (earnings) of subsidiaries, net of dividends or distributions			65,257	(195,285)
Provision (reversal) for loan losses			0	0
Goodwill impairment charge		0		0
Amortization of intangibles			0	0
Depreciation and amortization of premises and equipment			0	0
Net accretion of discounts and amortization of premiums and deferred fees			0	0
Impairment losses on long-lived assets			0
Other-than-temporary impairment on investment securities	0		0	0
Fair value adjustments on mortgage servicing rights			0	0
FDIC loss share (income) expense			0	0
Adjustments (expense) to indemnity reserves on loans sold	0	0	0	0
Earnings from investments under the equity method			0	0
Deferred income tax (benefit) expense			214	208
(Gain) loss on:
Disposition of premises and equipment			0	0
Sale and valuation adjustments of investment securities			0	0
Sale of loans, including valuation adjustments on loans held-for-sale and mortgage banking activities			0	0
Sale of foreclosed assets, including write-downs			0	0
Acquisitions of loans held-for-sale		0	0
Proceeds from sale of loans held-for-sale		0	0
Net originations on loans held-for-sale			0	0
Net (increase) decrease in:
Trading securities			(25)	121
Accrued income receivable			(15)	10
Other assets			15,193	(4,309)
Net increase (decrease) in:
Interest payable			15	(10)
Pension and other postretirement benefits obligation			0	0
Other liabilities			(8,919)	3,776
Total adjustments			71,720	195,081
Net Cash Provided By Used In Operating Activities			(173,544)	(78,006)
Cash flows from investing activities:
Net (increase) decrease in money market investments			(26,025)	12,965
Purchases of investment securities:
Available-for-sale			0	0
Other			0	0
Proceeds from calls, paydowns, maturities and redemptions of investment securities:
Available-for-sale			0	0
Held-to-maturity			0	0
Other				0
Proceeds from the sale of investment securities available-for-sale			0
Proceeds from sale of other investment securities			0	0
Net repayments on loans			0	0
Proceeds from sale of loans			(37,864)	0
Acquisition of loan portfolios			37,864	0
Acquisition of trademark			0
Net payments from FDIC under loss sharing agreements			0	0
Return of capital from equity method investments			0	0
Capital Contribution Subsidiaries			0
Return Of Capital From Wholly Owned Subsidiaries			(32,840)	(14,000)
Acquisition of premises and equipment			0	0
Proceeds from sale of:
Premises and equipment			0	0
Foreclosed assets			0	0
Net cash (used in) provided by investing activities			(58,865)	(1,035)
Net increase (decrease) in:
Deposits			29,485	3,607
Federal funds purchased and assets sold under agreements to repurchase			0	0
Other short-term borrowings			0
Payments of notes payable			0	0
Proceeds from issuance of notes payable			0	0
Proceeds from issuance of common stock			0	0
Cash Dividends Paid To Parent Company			179,500	78,100
Dividends paid			0	0
Net payments for repurchase of common stock			0	(93)
Return Of Capital To Parent Company			0	14,000
Capital contribution from parent			(5,955)
Payments related to tax witholding for shared-based compensation			32,840	0
Net cash (used in) provided by financing activities			235,870	95,614
Net (decrease) increase in cash and due from banks			3,461	16,573
Cash and due from banks at beginning of period			(48,081)	(24,844)	(24,844)
Cash and due from banks at end of period	(44,620)	(8,271)	(44,620)	(8,271)	(48,081)
Popular, Inc. Holding Co.
Cash flows from operating activities:
Net Income	20,664	46,810	209,835	220,796
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Equity in losses (earnings) of subsidiaries, net of dividends or distributions			(51,310)	(164,996)
Provision (reversal) for loan losses			309	(36)
Goodwill impairment charge		0		0
Amortization of intangibles			0	0
Depreciation and amortization of premises and equipment			480	497
Net accretion of discounts and amortization of premiums and deferred fees			1,565	1,565
Impairment losses on long-lived assets			0
Other-than-temporary impairment on investment securities	0		0	0
Fair value adjustments on mortgage servicing rights			0	0
FDIC loss share (income) expense			0	0
Adjustments (expense) to indemnity reserves on loans sold	0	0	0	0
Earnings from investments under the equity method			(10,728)	(9,070)
Deferred income tax (benefit) expense			0	1
(Gain) loss on:
Disposition of premises and equipment and other productive assets			(17)	(1)
Sale and valuation adjustments of investment securities			0	(1,767)
Sale of loans, including valuation adjustments on loans held-for-sale and mortgage banking activities			0	0
Sale of foreclosed assets, including write-downs			42	52
Acquisitions of loans held-for-sale			0	0
Proceeds from sale of loans held-for-sale			0	0
Net originations on loans held-for-sale			0	0
Net (increase) decrease in:
Trading securities			(961)	(475)
Accrued income receivable			(115)	(6)
Other assets			1,331	2,304
Net increase (decrease) in:
Interest payable			(7,875)	(7,875)
Pension and other postretirement benefits obligation			0	0
Other liabilities			2,115	(5,724)
Total adjustments			(65,164)	(185,531)
Net Cash Provided By Used In Operating Activities			144,671	35,265
Cash flows from investing activities:
Net (increase) decrease in money market investments			13,651	(22,111)
Purchases of investment securities:
Available-for-sale			0	0
Other			0	0
Proceeds from calls, paydowns, maturities and redemptions of investment securities:
Available-for-sale			0	0
Held-to-maturity			0	0
Other				0
Proceeds from the sale of investment securities available-for-sale			0	278
Proceeds from sale of other investment securities			0	1,583
Net repayments on loans			172	25
Proceeds from sale of loans			0	0
Acquisition of loan portfolios			(31,909)	0
Acquisition of trademark			(5,560)
Net payments from FDIC under loss sharing agreements			0	0
Return of capital from equity method investments			500	118
Capital Contribution Subsidiaries			(5,955)
Return Of Capital From Wholly Owned Subsidiaries			22,400	14,000
Acquisition of premises and equipment			(594)	(794)
Proceeds from sale of:
Premises and equipment and other productive assets			21	56
Foreclosed assets			39	434
Net cash (used in) provided by investing activities			(7,235)	(6,411)
Net increase (decrease) in:
Deposits			0	0
Federal funds purchased and assets sold under agreements to repurchase			0	0
Other short-term borrowings			0
Payments of notes payable			0	0
Proceeds from issuance of notes payable			0	0
Proceeds from issuance of common stock			5,515	5,718
Cash Dividends Paid To Parent Company			0	0
Dividends paid			(69,162)	(49,438)
Net payments for repurchase of common stock			(75,661)	(1,453)
Return Of Capital To Parent Company			0	0
Capital contribution from parent			0
Payments related to tax witholding for shared-based compensation			(1,756)	0
Net cash (used in) provided by financing activities			(141,064)	(45,173)
Net (decrease) increase in cash and due from banks			(3,628)	(16,319)
Cash and due from banks at beginning of period			47,783	24,298	24,298
Cash and due from banks at end of period	44,155	7,979	44,155	7,979	47,783
PNA Holding Co.
Cash flows from operating activities:
Net Income	(9,371)	7,587	9,987	23,346
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Equity in losses (earnings) of subsidiaries, net of dividends or distributions			(13,947)	(30,289)
Provision (reversal) for loan losses			0	0
Goodwill impairment charge		0		0
Amortization of intangibles			0	0
Depreciation and amortization of premises and equipment			0	0
Net accretion of discounts and amortization of premiums and deferred fees			0	21
Impairment losses on long-lived assets			0
Other-than-temporary impairment on investment securities	0		0	0
Fair value adjustments on mortgage servicing rights			0	0
FDIC loss share (income) expense			0	0
Adjustments (expense) to indemnity reserves on loans sold	0	0	0	0
Earnings from investments under the equity method			(1,256)	2,787
Deferred income tax (benefit) expense			(2,132)	(3,739)
(Gain) loss on:
Disposition of premises and equipment and other productive assets			0	0
Sale and valuation adjustments of investment securities			21	0
Sale of loans, including valuation adjustments on loans held-for-sale and mortgage banking activities			0	0
Sale of foreclosed assets, including write-downs			0	0
Acquisitions of loans held-for-sale			0	0
Proceeds from sale of loans held-for-sale			0	0
Net originations on loans held-for-sale			0	0
Net (increase) decrease in:
Trading securities			0	0
Accrued income receivable			107	80
Other assets			45	(26)
Net increase (decrease) in:
Interest payable			(2,685)	(2,685)
Pension and other postretirement benefits obligation			0	0
Other liabilities			(760)	(543)
Total adjustments			(20,607)	(34,394)
Net Cash Provided By Used In Operating Activities			(10,620)	(11,048)
Cash flows from investing activities:
Net (increase) decrease in money market investments			10,491	10,835
Purchases of investment securities:
Available-for-sale			0	0
Other			0	0
Proceeds from calls, paydowns, maturities and redemptions of investment securities:
Available-for-sale			0	0
Held-to-maturity			0	0
Other				0
Proceeds from the sale of investment securities available-for-sale			0	0
Proceeds from sale of other investment securities			0	0
Net repayments on loans			0	0
Proceeds from sale of loans			0	0
Acquisition of loan portfolios			0	0
Acquisition of trademark			0
Net payments from FDIC under loss sharing agreements			0	0
Return of capital from equity method investments			0	206
Capital Contribution Subsidiaries			0
Return Of Capital From Wholly Owned Subsidiaries			10,400	0
Acquisition of premises and equipment			0	0
Proceeds from sale of:
Premises and equipment and other productive assets			0	0
Foreclosed assets			0	0
Net cash (used in) provided by investing activities			20,891	11,041
Net increase (decrease) in:
Deposits			0	0
Federal funds purchased and assets sold under agreements to repurchase			0	0
Other short-term borrowings			0
Payments of notes payable			0	0
Proceeds from issuance of notes payable			0	0
Proceeds from issuance of common stock			0	0
Cash Dividends Paid To Parent Company			0	0
Dividends paid			0	0
Net payments for repurchase of common stock			0	0
Return Of Capital To Parent Company			(10,400)	0
Capital contribution from parent			0
Payments related to tax witholding for shared-based compensation			0	0
Net cash (used in) provided by financing activities			(10,400)	0
Net (decrease) increase in cash and due from banks			(129)	(7)
Cash and due from banks at beginning of period			591	600	600
Cash and due from banks at end of period	462	593	462	593	591
All other subsidiaries and eliminations
Cash flows from operating activities:
Net Income	31,138	52,772	235,277	249,741
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Equity in losses (earnings) of subsidiaries, net of dividends or distributions			0	0
Provision (reversal) for loan losses			253,627	128,687
Goodwill impairment charge		3,801		3,801
Amortization of intangibles			7,034	9,308
Depreciation and amortization of premises and equipment			35,486	34,228
Net accretion of discounts and amortization of premiums and deferred fees			(18,936)	(38,339)
Impairment losses on long-lived assets			11,286
Other-than-temporary impairment on investment securities	0		8,299	209
Fair value adjustments on mortgage servicing rights			24,262	18,879
FDIC loss share (income) expense			12,680	77,445
Adjustments (expense) to indemnity reserves on loans sold	6,406	4,390	11,302	14,234
Earnings from investments under the equity method			(15,366)	(17,529)
Deferred income tax (benefit) expense			32,389	65,448
(Gain) loss on:
Disposition of premises and equipment and other productive assets			5,035	3,604
Sale and valuation adjustments of investment securities			(305)	(165)
Sale of loans, including valuation adjustments on loans held-for-sale and mortgage banking activities			(16,455)	(32,982)
Sale of foreclosed assets, including write-downs			19,186	13,108
Acquisitions of loans held-for-sale			(204,813)	(223,189)
Proceeds from sale of loans held-for-sale			68,326	58,003
Net originations on loans held-for-sale			(283,709)	(365,353)
Net (increase) decrease in:
Trading securities			499,826	578,487
Accrued income receivable			(8,274)	4,459
Other assets			(3,115)	(26,170)
Net increase (decrease) in:
Interest payable			1,246	(983)
Pension and other postretirement benefits obligation			(13,760)	(56,537)
Other liabilities			22,742	(2,801)
Total adjustments			447,993	245,852
Net Cash Provided By Used In Operating Activities			683,270	495,593
Cash flows from investing activities:
Net (increase) decrease in money market investments			(2,596,111)	(1,785,091)
Purchases of investment securities:
Available-for-sale			(2,356,389)	(2,408,514)
Other			(23,822)	(14,017)
Proceeds from calls, paydowns, maturities and redemptions of investment securities:
Available-for-sale			1,225,915	951,447
Held-to-maturity			6,229	4,182
Other				11,051
Proceeds from the sale of investment securities available-for-sale			14,888	1,278
Proceeds from sale of other investment securities			17,675	6,423
Net repayments on loans			(77,572)	(93,379)
Proceeds from sale of loans			38,279	134,114
Acquisition of loan portfolios			(454,076)	(355,507)
Acquisition of trademark			5,560
Net payments from FDIC under loss sharing agreements			(11,520)	95,407
Return of capital from equity method investments			8,056	0
Capital Contribution Subsidiaries			5,955
Return Of Capital From Wholly Owned Subsidiaries			40	0
Acquisition of premises and equipment			(39,564)	(77,503)
Proceeds from sale of:
Premises and equipment and other productive assets			6,961	5,463
Foreclosed assets			85,666	54,166
Net cash (used in) provided by investing activities			(4,143,830)	(3,470,480)
Net increase (decrease) in:
Deposits			3,721,882	3,116,067
Federal funds purchased and assets sold under agreements to repurchase			(105,020)	3,106
Other short-term borrowings			239,398
Payments of notes payable			(89,375)	(230,608)
Proceeds from issuance of notes payable			45,000	165,047
Proceeds from issuance of common stock			0	0
Cash Dividends Paid To Parent Company			(179,500)	(78,100)
Dividends paid			0	0
Net payments for repurchase of common stock			(1)	(1)
Return Of Capital To Parent Company			10,400	(14,000)
Capital contribution from parent			5,955
Payments related to tax witholding for shared-based compensation			(32,840)	0
Net cash (used in) provided by financing activities			3,615,899	2,961,511
Net (decrease) increase in cash and due from banks			155,339	(13,376)
Cash and due from banks at beginning of period			362,101	363,620	363,620
Cash and due from banks at end of period	$ 517,440	$ 350,244	$ 517,440	$ 350,244	$ 362,101