Debt Securities Held-to-maturity - Weighted average yield and contractual maturities of debt securities HTM (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Amortized cost
Amortized Cost	$ 97,707	$ 101,575
Gross unrecognized gains
Gross Unrealized Gains	8,377	3,946
Gross unrealized losses
Gross Unrealized Losses	$ 2,166	$ 2,868
Weighted Average Yield
Weighted Average Yield	3.50%	3.60%
Obligations of Puerto Rico, States and political subdivisions
Amortized cost
Amortized cost - Within 1 year	$ 3,745	$ 3,510
Amortized cost - After 1 to 5 years	17,580	16,505
Amortized cost - After 5 to 10 years	18,195	23,885
Amortized cost - After 10 years	46,078	45,559
Amortized Cost	85,598	89,459
Gross unrecognized gains
Gross unrealized gains - Within 1 year	0	0
Gross unrealized gains - After 1 to 5 years	0	0
Gross unrealized gains - After 5 to 10 years	0	0
Gross unrealized gains - After 10 years	8,375	3,943
Gross Unrealized Gains	8,375	3,943
Gross unrealized losses
Gross unrealized losses - Within 1 year	33	36
Gross unrealized losses - After 1 to 5 years	269	1,081
Gross unrealized losses - After 5 to 10 years	1,861	1,704
Gross unrealized losses - After 10 years	2	47
Gross Unrealized Losses	2,165	2,868
Fair Value
Fair Value - within 1 year	3,712	3,474
Fair Value - After 1 to 5 years	17,311	15,424
Fair Value - After 5 to 10 years	16,334	22,181
Fair Value - After 10 years	54,451	49,455
Total investment securities held-to-maturity - Fair Value	$ 91,808	$ 90,534
Weighted Average Yield
Weighted average yield - Within 1 Year	6.02%	5.99%
Weighted average yield - After 1 to 5 years	6.11%	6.07%
Weighted average yield - After 5 to 10 years	3.11%	3.61%
Weighted average yield - After 10 years	1.69%	1.79%
Weighted Average Yield	3.09%	3.23%
Collateralized Mortgage Obligations - Federal agencies
Amortized cost
Amortized cost - After 1 to 5 years	$ 48
Amortized cost - After 5 to 10 years		$ 55
Amortized Cost	48	55
Gross unrecognized gains
Gross unrealized gains - After 1 to 5 years	2
Gross unrealized gains - After 5 to 10 years		3
Gross Unrealized Gains	2	3
Gross unrealized losses
Gross unrealized losses - After 1 to 5 years	0
Gross unrealized losses - After 5 to 10 years		0
Gross Unrealized Losses	0	0
Fair Value
Fair Value - After 1 to 5 years	50
Fair Value - After 5 to 10 years		58
Total investment securities held-to-maturity - Fair Value	$ 50	$ 58
Weighted Average Yield
Weighted average yield - After 1 to 5 years	6.44%
Weighted average yield - After 5 to 10 years		5.45%
Weighted Average Yield	6.44%	5.45%
Securities in wholly owned statutory business trusts
Amortized cost
Amortized cost - After 10 years	$ 11,561	$ 11,561
Amortized Cost	11,561	11,561
Gross unrecognized gains
Gross unrealized gains - After 10 years	0	0
Gross Unrealized Gains	0	0
Gross unrealized losses
Gross unrealized losses - After 10 years	0	0
Gross Unrealized Losses	0	0
Fair Value
Fair Value - After 10 years	11,561	11,561
Total investment securities held-to-maturity - Fair Value	$ 11,561	$ 11,561
Weighted Average Yield
Weighted average yield - After 10 years	6.51%	6.51%
Weighted Average Yield	6.51%	6.51%
Other
Amortized cost
Amortized cost - After 1 to 5 years	$ 500	$ 500
Amortized Cost	500	500
Gross unrecognized gains
Gross unrealized gains - After 1 to 5 years	0	0
Gross Unrealized Gains	0	0
Gross unrealized losses
Gross unrealized losses - After 1 to 5 years	1	0
Gross Unrealized Losses	1	0
Fair Value
Fair Value - After 1 to 5 years	499	500
Total investment securities held-to-maturity - Fair Value	$ 499	$ 500
Weighted Average Yield
Weighted average yield - After 1 to 5 years	2.97%	2.97%
Weighted Average Yield	2.97%	2.97%

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