Debt Securities Held-to-maturity - HTM debt securities in a continuous unrealized loss position (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Debt Securities, Held-to-maturity
Less than 12 months Fair Value	$ 22,926	$ 27,471
Less than 12 months Gross Unrealized Losses	319	1,165
12 months or more Fair Value	9,713	13,307
12 months or more Gross Unrealized Losses	1,847	1,703
Total Fair Value	32,639	40,778
Total Gross Unrealized Losses	2,166	2,868
Obligations of Puerto Rico, States and political subdivisions
Debt Securities, Held-to-maturity
Less than 12 months Fair Value	22,427	27,471
Less than 12 months Gross Unrealized Losses	318	1,165
12 months or more Fair Value	9,713	13,307
12 months or more Gross Unrealized Losses	1,847	1,703
Total Fair Value	32,140	40,778
Total Gross Unrealized Losses	2,165	$ 2,868
Other
Debt Securities, Held-to-maturity
Less than 12 months Fair Value	499
Less than 12 months Gross Unrealized Losses	1
12 months or more Fair Value	0
12 months or more Gross Unrealized Losses	0
Total Fair Value	499
Total Gross Unrealized Losses	$ 1

Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity), in continuous loss position for 12 months or longer.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27337-111563

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 50
-Paragraph 6
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563

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Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity), in unrealized loss position.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563

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Fair value of investment in debt security measured at amortized cost (held-to-maturity), in unrealized loss position.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563

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Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity), in continuous loss position for less than 12 months.

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Fair value of investment in debt security measured at amortized cost (held-to-maturity), in continuous unrealized loss position for less than 12 months.

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Fair value of investment in debt security measured at amortized cost (held-to-maturity), in continuous unrealized loss position for 12 months or longer.

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