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SECURITIES - Investment Securities Available for Sale in Continuous Unrealized Loss Position (Details) - USD ($) $ in Thousands | Dec. 31, 2017 | Dec. 31, 2016
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Available-for-sale securities in a continuous unrealized loss position, fair value [Abstract] |  |
Less than 12 months | $ 123,007 | $ 259,567
12 months or longer | 131,436 | 225
Total | 254,443 | 259,792
Available-for-sale securities in a continuous unrealized loss position, unrealized losses [Abstract] |  |
Less than 12 months | 1,199 | 7,804
12 months or longer | 4,171 | 1
Total | 5,370 | 7,805
Obligations of U.S. Government and U.S. Government sponsored enterprises |  |
Available-for-sale securities in a continuous unrealized loss position, fair value [Abstract] |  |
Less than 12 months | 14,982 |
12 months or longer | 0 |
Total | 14,982 |
Available-for-sale securities in a continuous unrealized loss position, unrealized losses [Abstract] |  |
Less than 12 months | 21 |
12 months or longer | 0 |
Total | 21 |
Mortgage-backed securities, residential |  |
Available-for-sale securities in a continuous unrealized loss position, fair value [Abstract] |  |
Less than 12 months | 83,562 | 233,843
12 months or longer | 131,165 | 0
Total | 214,727 | 233,843
Available-for-sale securities in a continuous unrealized loss position, unrealized losses [Abstract] |  |
Less than 12 months | 1,013 | 7,492
12 months or longer | 4,153 | 0
Total | 5,166 | 7,492
Obligations of states and political subdivisions |  |
Available-for-sale securities in a continuous unrealized loss position, fair value [Abstract] |  |
Less than 12 months | 20,526 | 25,724
12 months or longer | 271 | 0
Total | 20,797 | 25,724
Available-for-sale securities in a continuous unrealized loss position, unrealized losses [Abstract] |  |
Less than 12 months | 133 | 312
12 months or longer | 18 | 0
Total | 151 | 312
SBA loan pools |  |
Available-for-sale securities in a continuous unrealized loss position, fair value [Abstract] |  |
Less than 12 months | 3,937 | 0
12 months or longer | 0 | 225
Total | 3,937 | 225
Available-for-sale securities in a continuous unrealized loss position, unrealized losses [Abstract] |  |
Less than 12 months | 32 | 0
12 months or longer | 0 | 1
Total | $ 32 | $ 1

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- Definition Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for twelve months or longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -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 Reference 2: http://www.xbrl.org/2003/role/presentationRef -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 + Details
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- Definition Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale in a continuous loss position. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -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://www.xbrl.org/2003/role/presentationRef -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 + Details
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- Definition This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -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 + Details
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- Definition Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for less than twelve months. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -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 Reference 2: http://www.xbrl.org/2003/role/presentationRef -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 + Details
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