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LOW INCOME HOUSING PROJECT INVESTMENTS Low Income Housing Project Investments (Details) - USD ($) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2017 | Sep. 30, 2017 | Jun. 30, 2017 | Mar. 31, 2017 | Dec. 31, 2016 | Sep. 30, 2016 | Jun. 30, 2016 | Mar. 31, 2016 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Tax Expense related to a change in tax law | $ 2,361,000 | $ 0 | $ 0 | $ 0 | $ 0 | $ 0 | $ 0 | $ 0 | $ 466,000 |  | $ 0 | $ 0
Original Investment in Low Income Housing Projects | 47,399,000 |  |  |  | 47,379,000 |  |  |  | 47,399,000 |  | 47,379,000 | 42,199,000
Amortization Method Qualified Affordable Housing Project Investments | 35,225,000 |  |  |  | 39,606,000 |  |  |  | 35,225,000 |  | 39,606,000 | 38,151,000
Qualified Affordable Housing Project Investments, Commitment | 4,536,000 |  |  |  | $ 12,161,000 |  |  |  | 4,536,000 |  | 12,161,000 | 14,607,000
Affordable Housing Tax Credits and Other Tax Benefits, Amount |  |  |  |  |  |  |  |  | 5,654,000 |  | 5,366,000 | 3,632,000
Amortization Method Qualified Affordable Housing Project Investments, Amortization |  |  |  |  |  |  |  |  | 4,402,000 | [1] | 3,725,000 | 2,450,000
Income (Loss) from Affordable Housing Projects, Equity Method Investments |  |  |  |  |  |  |  |  | 1,253,000 |  | $ 1,641,000 | $ 1,182,000
Investments in Low Income Housing Projects [Member] |  |  |  |  |  |  |  |  |  |  |  |
Tax Expense related to a change in tax law | $ 466,000 |  |  |  |  |  |  |  | $ 466,000 |  |  |
[1] | The 2017 amount is inclusive of $466,000 related to the revaluation of Low Income Housing tax credit investments as a result of the 2017 Tax Act.

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- Definition Amount of affordable housing tax credits and other tax benefits recognized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 740 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=64813897&loc=SL49122993-202985 + Details
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- Definition Amount of investment in qualified affordable housing projects. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 740 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=64813897&loc=SL49122993-202985 + Details
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- Definition Amount of amortization expense of investment in qualified affordable housing projects. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 740 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=64813897&loc=SL49122993-202985 + Details
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- Definition Amount of investment income (loss) of qualified affordable housing project investments accounted for using the equity method. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 740 -Section 50 -Paragraph 2 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=64813897&loc=SL49122993-202985 + Details
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- Definition Amount of commitment or contingent commitments to qualified affordable housing project investments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 740 -Section 50 -Paragraph 2 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=64813897&loc=SL49122993-202985 + Details
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