Note Investment Securities Held-to-maturity (Amortized cost, gross unrealized gains and losses, approximate fair value, weighted average yield and contractual maturities of investment securities HTM) (Detail) - USD ($) $ in Thousands	Mar. 31, 2017		Dec. 31, 2016
Schedule of Held-to-maturity Securities [Line Items]
Investment securities held-to-maturity, fair value	$ 73,628	[1]	$ 75,576	[2]
Gross Unrealized Gains	1,391		1,372
Gross Unrealized Losses	24,089		23,897
Amortized Cost	$ 96,326	[1]	$ 98,101	[2]
Weighted Average Yield	3.42%		3.46%
Obligations of Puerto Rico, States and political subdivisions
Schedule of Held-to-maturity Securities [Line Items]
Investment securities held-to-maturity, fair value	$ 71,589		$ 73,540
Gross Unrealized Gains	1,387		1,368
Gross Unrealized Losses	24,051		23,855
Amortized Cost	$ 94,253		$ 96,027
Weighted Average Yield	3.45%		3.49%
Obligations of Puerto Rico, States and political subdivisions | Within 1 year
Schedule of Held-to-maturity Securities [Line Items]
Investment securities held-to-maturity, fair value	$ 1,860		$ 1,865
Gross Unrealized Gains	0		0
Gross Unrealized Losses	1,375		1,240
Amortized Cost	$ 3,235		$ 3,105
Weighted Average Yield	5.95%		5.90%
Obligations of Puerto Rico, States and political subdivisions | After 1 and within 5 years
Schedule of Held-to-maturity Securities [Line Items]
Investment securities held-to-maturity, fair value	$ 8,573		$ 8,583
Gross Unrealized Gains	0		0
Gross Unrealized Losses	6,627		5,957
Amortized Cost	$ 15,200		$ 14,540
Weighted Average Yield	6.03%		6.02%
Obligations of Puerto Rico, States and political subdivisions | After 5 to 10 years
Schedule of Held-to-maturity Securities [Line Items]
Investment securities held-to-maturity, fair value	$ 9,796		$ 10,869
Gross Unrealized Gains	0		0
Gross Unrealized Losses	7,689		7,766
Amortized Cost	$ 17,485		$ 18,635
Weighted Average Yield	6.24%		6.20%
Obligations of Puerto Rico, States and political subdivisions | After 10 years
Schedule of Held-to-maturity Securities [Line Items]
Investment securities held-to-maturity, fair value	$ 51,360		$ 52,223
Gross Unrealized Gains	1,387		1,368
Gross Unrealized Losses	8,360		8,892
Amortized Cost	$ 58,333		$ 59,747
Weighted Average Yield	1.80%		1.91%
Collateralized Mortgage Obligations - Federal agencies
Schedule of Held-to-maturity Securities [Line Items]
Investment securities held-to-maturity, fair value	$ 77		$ 78
Gross Unrealized Gains	4		4
Gross Unrealized Losses	0		0
Amortized Cost	$ 73		$ 74
Weighted Average Yield	5.45%		5.45%
Collateralized Mortgage Obligations - Federal agencies | After 5 to 10 years
Schedule of Held-to-maturity Securities [Line Items]
Investment securities held-to-maturity, fair value	$ 77		$ 78
Gross Unrealized Gains	4		4
Gross Unrealized Losses	0		0
Amortized Cost	$ 73		$ 74
Weighted Average Yield	5.45%		5.45%
Other
Schedule of Held-to-maturity Securities [Line Items]
Investment securities held-to-maturity, fair value	$ 1,962		$ 1,958
Gross Unrealized Gains	0		0
Gross Unrealized Losses	38		42
Amortized Cost	$ 2,000		$ 2,000
Weighted Average Yield	2.04%		2.05%
Other | Within 1 year
Schedule of Held-to-maturity Securities [Line Items]
Investment securities held-to-maturity, fair value	$ 1,225		$ 997
Gross Unrealized Gains	0		0
Gross Unrealized Losses	25		3
Amortized Cost	$ 1,250		$ 1,000
Weighted Average Yield	1.62%		1.65%
Other | After 1 and within 5 years
Schedule of Held-to-maturity Securities [Line Items]
Investment securities held-to-maturity, fair value	$ 737		$ 961
Gross Unrealized Gains	0		0
Gross Unrealized Losses	13		39
Amortized Cost	$ 750		$ 1,000
Weighted Average Yield	2.75%		2.44%

[1] Includes $94.3 million pledged to secure public and trust deposits that the secured parties are not permitted to sell or repledge the collateral.

[2] Includes $53.1 million pledged to secure public and trust deposits that the secured parties are not permitted to sell or repledge the collateral.