INVESTMENT SECURITIES - OTTI Losses on Available-for-Sale Debt Securities (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016		Dec. 31, 2015	Jun. 30, 2015	Mar. 31, 2015
Schedule Of Available For Sale Securities [Line Items]
Total other-than-temporary impairment losses	$ (1,845)				$ 0
Net impairment losses recognized in earnings	(6,687)				(156)
Mortgage Backed Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Total other-than-temporary impairment losses	(1,845)				0
Portion of loss previously recognized in other comprehensive income	(4,842)				(156)
Net impairment losses recognized in earnings	$ (6,687)	[1]			$ (156)	[2]
US States And Political Subdivisions Member [Member]
Schedule Of Available For Sale Securities [Line Items]
Net impairment losses recognized in earnings			$ (3,000)	$ (12,900)

[1] (1) For the quarter ended March 31, 2016, approximately $6.3 million of the credit impairment recognized in earnings consisted of credit losses on Puerto Rico Government debt securities and $0.4 million was associated with credit losses on private label MBS.

[2] (2) The $0.2 million credit impairment recognized in earnings in the first quarter of 2015 was associated with private label MBS.