Fair values of major classes of identifiable assets acquired and liabilities assumed (Detail) - Entity [Domain] - USD ($) $ in Thousands		Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Jun. 30, 2014	Dec. 31, 2013
Business Acquisition [Line Items]
Goodwill		$ 505,435		$ 465,676	$ 461,246	$ 647,757
FDIC Assisted Partial Acquisition Of Doral Bank [Member]
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Cash And Equivalents			$ 339,633
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Intangible Assets Other Than Goodwill			23,572
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Assets Other			75,245
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Assets			2,757,226
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Liabilities			2,799,370
Goodwill			42,144
FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Investment in Federal Home Loan Bank Stock [Member]
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Assets Marketable Securities			30,785
FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Accrued Income Receivable [Member]
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Assets Receivables Combination Recognized IdentifiableAssets Acquired And Liabilities Assumed Current Assets Receivables			7,808
FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Loans Member
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Assets Receivables Combination Recognized IdentifiableAssets Acquired And Liabilities Assumed Current Assets Receivables			1,665,756
FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Available For Sale Securities Member
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Assets Marketable Securities			172,706
FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Notes Receivable from FDIC [Member]
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Assets Receivables Combination Recognized IdentifiableAssets Acquired And Liabilities Assumed Current Assets Receivables			441,721
FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Deposits Member
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Liabilities Other			2,201,455
FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Federal Home Loan Bank
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Liabilities Other			547,187
FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Other Liabilities Member
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Liabilities Other			50,728
FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Preliminary Allocation [Member]
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Cash And Equivalents			339,633
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Intangible Assets Other Than Goodwill			23,572
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Assets Other			67,676
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Assets			2,360,388
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Liabilities			2,786,132
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Net			425,744
FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Preliminary Allocation [Member] | Investment in Federal Home Loan Bank Stock [Member]
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Assets Marketable Securities			30,785
FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Preliminary Allocation [Member] | Accrued Income Receivable [Member]
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Assets Receivables Combination Recognized IdentifiableAssets Acquired And Liabilities Assumed Current Assets Receivables			7,808
FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Preliminary Allocation [Member] | Loans Member
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Assets Receivables Combination Recognized IdentifiableAssets Acquired And Liabilities Assumed Current Assets Receivables			1,718,208
FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Preliminary Allocation [Member] | Available For Sale Securities Member
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Assets Marketable Securities			172,706
FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Preliminary Allocation [Member] | Notes Receivable from FDIC [Member]
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Assets Receivables Combination Recognized IdentifiableAssets Acquired And Liabilities Assumed Current Assets Receivables			0
FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Preliminary Allocation [Member] | Deposits Member
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Liabilities Other			2,193,404
FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Preliminary Allocation [Member] | Federal Home Loan Bank
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Liabilities Other			542,000
FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Preliminary Allocation [Member] | Other Liabilities Member
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Liabilities Other			50,728
FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Fair Value Adjustment [Member]
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Cash And Equivalents			0
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Intangible Assets Other Than Goodwill			0
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Assets Other			7,569
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Assets			(44,883)
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Liabilities			13,238
Business Combination Aggregate Fair Value Adjustments			(58,121)
FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Fair Value Adjustment [Member] | Investment in Federal Home Loan Bank Stock [Member]
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Assets Marketable Securities			0
FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Fair Value Adjustment [Member] | Accrued Income Receivable [Member]
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Assets Receivables Combination Recognized IdentifiableAssets Acquired And Liabilities Assumed Current Assets Receivables			0
FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Fair Value Adjustment [Member] | Loans Member
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Assets Receivables Combination Recognized IdentifiableAssets Acquired And Liabilities Assumed Current Assets Receivables			(52,452)
FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Fair Value Adjustment [Member] | Available For Sale Securities Member
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Assets Marketable Securities			0
FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Fair Value Adjustment [Member] | Notes Receivable from FDIC [Member]
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Assets Receivables Combination Recognized IdentifiableAssets Acquired And Liabilities Assumed Current Assets Receivables			0
FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Fair Value Adjustment [Member] | Deposits Member
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Liabilities Other			8,051
FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Fair Value Adjustment [Member] | Federal Home Loan Bank
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Liabilities Other			5,187
FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Fair Value Adjustment [Member] | Other Liabilities Member
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Liabilities Other			0
FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Other Adjustments [Member]
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Cash And Equivalents	[1]		0
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Intangible Assets Other Than Goodwill	[1]		0
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Assets Other	[1]		0
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Assets	[1]		441,721
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Liabilities	[1]		0
Business Combination Total Other Adjustments	[1]		441,721
FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Other Adjustments [Member] | Investment in Federal Home Loan Bank Stock [Member]
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Assets Marketable Securities	[1]		0
FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Other Adjustments [Member] | Accrued Income Receivable [Member]
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Assets Receivables Combination Recognized IdentifiableAssets Acquired And Liabilities Assumed Current Assets Receivables	[1]		0
FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Other Adjustments [Member] | Loans Member
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Assets Receivables Combination Recognized IdentifiableAssets Acquired And Liabilities Assumed Current Assets Receivables	[1]		0
FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Other Adjustments [Member] | Available For Sale Securities Member
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Assets Marketable Securities	[1]		0
FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Other Adjustments [Member] | Notes Receivable from FDIC [Member]
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Assets Receivables Combination Recognized IdentifiableAssets Acquired And Liabilities Assumed Current Assets Receivables	[1]		441,721
FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Other Adjustments [Member] | Deposits Member
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Liabilities Other	[1]		0
FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Other Adjustments [Member] | Federal Home Loan Bank
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Liabilities Other	[1]		0
FDIC Assisted Partial Acquisition Of Doral Bank [Member] | Other Adjustments [Member] | Other Liabilities Member
Business Acquisition [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Liabilities Other	[1]		$ 0

[1] The additional consideration represents the cash to be received from the FDIC for the difference between the net liabilities assumed and the net premium paid on the transaction.