INVESTMENT SECURITIES (Gross Unrealized Loss and Fair Value of HTM Debt Securities) (Details) (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Fair Value
Less than 12 months	$ 81,040	$ 1,290,503
12 months or longer	0	657,733
Unrealized Losses
Less than 12 months	(930)	(7,373)
12 months or longer	0	(5,666)
GNMA - Residential
Fair Value
Less than 12 months	81,040	559,058
12 months or longer	0	657,733
Unrealized Losses
Less than 12 months	(930)	(2,004)
12 months or longer	0	(5,666)
GNMA - Commercial
Fair Value
Less than 12 months	0	731,445
12 months or longer	0	0
Unrealized Losses
Less than 12 months	0	(5,369)
12 months or longer	$ 0	$ 0

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
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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.

+ 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=121645371&loc=d3e27290-111563

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 320
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27337-111563

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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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