Business Combination - Additional Information (Detail) - USD ($)	3 Months Ended	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2015	Apr. 23, 2015	Mar. 31, 2015	Feb. 23, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Business Combination Contingent Consideration Asset	$ 0	$ 0				$ 0
FDIC Assisted Partial Acquisition Of Doral Bank [Member]
Business Acquisition [Line Items]
Business Acquisition Name Of Acquired Entity		Doral Bank
Business Acquisition Date Of Acquisition Agreement1		Feb. 27, 2015
Revenues Net Of Interest Expense	34,400,000	$ 48,400,000
Operating Expenses	26,800,000	41,300,000
Business Acquisition, Cost Of Servicing Asset Purchase Price	56,200,000	56,200,000
FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Fair Value Adjustment [Member] | Doral Bank Transaction MSR FV Retro Adjustment [Member]
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Assets Other	(2,100,000)	(2,100,000)
FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Fair Value Adjustment [Member] | Doral Bank Transaction Deposits Premium FV Retro Adjustment [Member]
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Assets	$ 2,600,000	$ 2,600,000
Loans Member | FDIC Assisted Partial Acquisition Of Doral Bank [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Financial Assets				$ 1,700,000,000
Deposits Member | FDIC Assisted Partial Acquisition Of Doral Bank [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Financial Liabilities				2,200,000,000
Core Deposits Member | FDIC Assisted Partial Acquisition Of Doral Bank [Member]
Business Acquisition [Line Items]
Finite-Lived Intangible Assets, Useful Life		15 years
Banco Popular De Puerto Rico [Member] | FDIC Assisted Partial Acquisition Of Doral Bank [Member]
Business Acquisition [Line Items]
Principal Amount Outstanding on Loans Securitized or Asset-backed Financing Arrangement					$ 5,000,000,000
Business Acquisition, Cost of Servicing Asset, Estimated Purchase Price					$ 48,600,000
Banco Popular De Puerto Rico [Member] | FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Government National Mortgage Association Certificates And Obligations GNMA Member
Business Acquisition [Line Items]
Principal Amount Outstanding on Loans Securitized or Asset-backed Financing Arrangement			$ 2,700,000,000
Banco Popular De Puerto Rico [Member] | Loans Member | FDIC Assisted Partial Acquisition Of Doral Bank [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Financial Assets				827,000,000
Banco Popular De Puerto Rico [Member] | Deposits Member | FDIC Assisted Partial Acquisition Of Doral Bank [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Financial Liabilities				574,000,000
Banco Popular De Puerto Rico [Member] | Deposits Member | FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Online Platform [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Financial Liabilities				425,000,000
Bpna [Member] | Loans Member | FDIC Assisted Partial Acquisition Of Doral Bank [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Financial Assets				891,000,000
Bpna [Member] | Deposits Member | FDIC Assisted Partial Acquisition Of Doral Bank [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Financial Liabilities				$ 1,200,000,000