Note Loans (Non-covered loans HIP in past due status, non-performing status and accruing loans past-due 90 days or more by loan class) (Parenthetical) (Detail) - USD ($) $ in Thousands	Mar. 31, 2019		Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unearned Income	$ 160,579		$ 155,824
Loans held-for-sale, at lower of cost or fair value	43,985		51,422
Loans held-in-portfolio, net of unearned income	26,647,708		26,507,889
Non Covered Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Pledged Financial Instruments, Not Separately Reported, Loans Receivable Pledged as Collateral	6,600,000		6,900,000
Loans-held-in portfolio served as collateral to secure credit facilities authorized with the FHLB	4,600,000		4,800,000
Loans held-in-portfolio, net of unearned income	26,647,708	[1],[2]	26,507,889	[3],[4]
FRB Discount Window | Non Covered Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans served as collateral to secure debt obligations	2,000,000		2,100,000
PUERTO RICO
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held-in-portfolio, net of unearned income	19,996,350		19,883,472
PUERTO RICO | Non Covered Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held-in-portfolio, net of unearned income	19,996,350		19,883,472
Popular U.S.
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held-in-portfolio, net of unearned income	6,651,358		6,624,417
Popular U.S. | Non Covered Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held-in-portfolio, net of unearned income	6,651,358		6,624,417
ASC Subtopic 310-30 | Non Covered Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held-in-portfolio, net of unearned income	257,000		216,000
ASC Subtopic 310-30 | PUERTO RICO | Non Covered Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held-in-portfolio, net of unearned income	194,000		143,000
ASC Subtopic 310-30 | Popular U.S. | Non Covered Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held-in-portfolio, net of unearned income	$ 63,000		$ 73,000

[1] Includes $6.6 billion pledged to secure credit facilities and public funds that the secured parties are not permitted to sell or repledge the collateral, of which $4.6 billion were pledged at the Federal Home Loan Bank ("FHLB") as collateral for borrowings and $2.0 billion at the Federal Reserve Bank ("FRB") for discount window borrowings.

[2] Loans held-in-portfolio are net of $161 million in unearned income and exclude $44 million in loans held-for-sale.

[3] Includes $6.9 billion pledged to secure credit facilities and public funds that the secured parties are not permitted to sell or repledge the collateral, of which $4.8 billion were pledged at the FHLB as collateral for borrowings and $2.1 billion at the FRB for discount window borrowings.

[4] Loans held-in-portfolio are net of $156 million in unearned income and exclude $51 million in loans held-for-sale.