Segment reporting - Results of Operations (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Segment Reporting Information
Net Interest income (expense)	$ 489,393	$ 461,021	$ 1,456,307	$ 1,384,997
Provision for credit losses (benefit)	(61,173)	19,138	(160,414)	271,318
Non interest Income	169,258	128,767	477,451	367,465
Amortization of intangibles	783	1,076	3,089	5,345
Depreciation expense	13,008	14,518	41,416	43,419
Other operating expenses	374,377	345,472	1,087,376	1,033,141
Income tax expense (benefit)	83,542	41,168	233,466	68,893
Net income (loss) from continuing operations	248,114	168,416	728,825	330,346
Segment assets	74,189,163	65,910,369	74,189,163	65,910,369	$ 65,926,000
Reportable Segment
Segment Reporting Information
Net Interest income (expense)	499,206	471,145	1,486,644	1,414,335
Provision for credit losses (benefit)	(60,959)	19,058	(160,226)	271,101
Non interest Income	152,153	114,625	434,071	333,939
Amortization of intangibles	783	1,052	2,837	5,272
Depreciation expense	12,680	14,259	40,556	42,678
Other operating expenses	374,729	347,071	1,090,767	1,036,779
Income tax expense (benefit)	83,496	41,184	234,121	69,706
Net income (loss) from continuing operations	240,630	163,146	712,660	322,738
Segment assets	73,791,528	65,581,429	73,791,528	65,581,429
Intersegment Elimination
Segment Reporting Information
Net Interest income (expense)	2	2	5	9
Provision for credit losses (benefit)	0	0	0	0
Non interest Income	(136)	(138)	(411)	(414)
Amortization of intangibles	0	0	0	0
Depreciation expense	0	0	0	0
Other operating expenses	(136)	(136)	(408)	(408)
Income tax expense (benefit)	0	0	0	0
Net income (loss) from continuing operations	2	0	2	3
Segment assets	(23,074)	(28,177)	(23,074)	(28,177)
Corporate
Segment Reporting Information
Net Interest income (expense)	(9,813)	(10,124)	(30,337)	(29,338)
Provision for credit losses (benefit)	(214)	80	(188)	217
Non interest Income	17,251	14,230	45,675	35,645
Amortization of intangibles	0	24	252	73
Depreciation expense	328	259	860	741
Other operating expenses	615	(748)	(567)	(1,056)
Income tax expense (benefit)	(279)	(312)	(925)	(964)
Net income (loss) from continuing operations	6,988	4,803	15,906	7,296
Segment assets	5,378,819	5,201,316	5,378,819	5,201,316
Eliminations
Segment Reporting Information
Net Interest income (expense)	0	0	0	0
Provision for credit losses (benefit)	0	0	0	0
Non interest Income	(146)	(88)	(2,295)	(2,119)
Amortization of intangibles	0	0	0	0
Depreciation expense	0	0	0	0
Other operating expenses	(967)	(851)	(2,824)	(2,582)
Income tax expense (benefit)	325	296	270	151
Net income (loss) from continuing operations	496	467	259	312
Segment assets	(4,981,184)	(4,872,376)	(4,981,184)	(4,872,376)
Banco Popular de Puerto Rico | Reportable Segment
Segment Reporting Information
Net Interest income (expense)	419,166	394,662	1,248,689	1,191,452
Provision for credit losses (benefit)	(37,022)	7,288	(104,425)	180,659
Non interest Income	146,139	107,577	417,399	315,522
Amortization of intangibles	617	886	2,338	4,773
Depreciation expense	11,164	11,921	35,115	36,282
Other operating expenses	324,171	292,528	938,754	876,438
Income tax expense (benefit)	65,357	35,834	187,784	69,040
Net income (loss) from continuing operations	201,018	153,782	606,522	339,782
Segment assets	63,476,269	55,388,782	63,476,269	55,388,782
Banco Popular de Puerto Rico | Reportable Segment | Commercial Banking
Segment Reporting Information
Net Interest income (expense)	183,456	164,791	543,807	486,050
Provision for credit losses (benefit)	(11,948)	4,061	(57,305)	23,244
Non interest Income	36,662	24,804	91,235	74,771
Amortization of intangibles	54	50	161	148
Depreciation expense	4,881	5,179	15,401	15,406
Other operating expenses	96,414	77,906	273,374	226,232
Income tax expense (benefit)	46,183	32,331	132,632	82,271
Net income (loss) from continuing operations	84,534	70,068	270,779	213,520
Segment assets	63,743,047	47,920,631	63,743,047	47,920,631
Banco Popular de Puerto Rico | Reportable Segment | Consumer and Retail Banking
Segment Reporting Information
Net Interest income (expense)	234,477	228,293	701,018	694,983
Provision for credit losses (benefit)	(25,074)	3,227	(47,120)	157,415
Non interest Income	83,531	58,955	251,022	170,205
Amortization of intangibles	457	699	1,845	2,911
Depreciation expense	6,124	6,569	19,222	20,383
Other operating expenses	206,257	195,624	599,289	587,297
Income tax expense (benefit)	17,836	2,275	51,531	(18,912)
Net income (loss) from continuing operations	112,408	78,854	327,273	116,094
Segment assets	30,902,005	29,358,230	30,902,005	29,358,230
Banco Popular de Puerto Rico | Reportable Segment | Other Financial Services
Segment Reporting Information
Net Interest income (expense)	1,233	1,578	3,864	10,419
Provision for credit losses (benefit)	0	0	0	0
Non interest Income	26,335	24,194	76,322	71,459
Amortization of intangibles	106	137	332	1,714
Depreciation expense	159	173	492	493
Other operating expenses	21,911	19,389	67,417	63,863
Income tax expense (benefit)	1,338	1,228	3,621	5,681
Net income (loss) from continuing operations	4,054	4,845	8,324	10,127
Segment assets	2,020,629	2,408,998	2,020,629	2,408,998
Banco Popular de Puerto Rico | Reportable Segment | Eliminations
Segment Reporting Information
Net Interest income (expense)	0	0	0	0
Provision for credit losses (benefit)	0	0	0	0
Non interest Income	(389)	(376)	(1,180)	(913)
Amortization of intangibles	0	0	0	0
Depreciation expense	0	0	0	0
Other operating expenses	(411)	(391)	(1,326)	(954)
Income tax expense (benefit)	0	0	0	0
Net income (loss) from continuing operations	22	15	146	41
Segment assets	(33,189,412)	(24,299,077)	(33,189,412)	(24,299,077)
PB | Reportable Segment
Segment Reporting Information
Net Interest income (expense)	80,038	76,481	237,950	222,874
Provision for credit losses (benefit)	(23,937)	11,770	(55,801)	90,442
Non interest Income	6,150	7,186	17,083	18,831
Amortization of intangibles	166	166	499	499
Depreciation expense	1,516	2,338	5,441	6,396
Other operating expenses	50,694	54,679	152,421	160,749
Income tax expense (benefit)	18,139	5,350	46,337	666
Net income (loss) from continuing operations	39,610	9,364	106,136	(17,047)
Segment assets	$ 10,338,333	$ 10,220,824	$ 10,338,333	$ 10,220,824