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BORROWINGS, Contractual Maturity on Borrowings (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016
Debt Instrument [Line Items] |  |
Carrying value | $ 485,896 | $ 248,370
Weighted-average rate at period end | 1.34% |
Weighted-average interest rate on borrowings during period | 1.51% | 1.46%
January 2, 2018 [Member] |  |
Debt Instrument [Line Items] |  |
Carrying value | $ 361,011 |
Weighted-average rate at period end | 0.54% |
July 3, 2023 [Member] |  |
Debt Instrument [Line Items] |  |
Carrying value | $ 601 |
Weighted-average rate at period end | 2.25% |
October 23, 2023 [Member] |  |
Debt Instrument [Line Items] |  |
Carrying value | $ 515 |
Weighted-average rate at period end | 1.50% |
October 1, 2025 [Member] |  |
Debt Instrument [Line Items] |  |
Carrying value | $ 329 |
Weighted-average rate at period end | 1.50% |
March 1, 2029 [Member] |  |
Debt Instrument [Line Items] |  |
Carrying value | $ 626 |
Weighted-average rate at period end | 2.50% |
July 31, 2031 [Member] |  |
Debt Instrument [Line Items] |  |
Carrying value | $ 24,875 |
Weighted-average rate at period end | 4.96% |
December 15, 2034 [Member] |  |
Debt Instrument [Line Items] |  |
Carrying value | $ 20,619 |
Weighted-average rate at period end | 3.54% |
December 15, 2036 [Member] |  |
Debt Instrument [Line Items] |  |
Carrying value | $ 77,320 |
Weighted-average rate at period end | 3.24% |

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- Definition The average effective interest rate during the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Amount of long-term debt and capital lease obligations including current maturities. + References No definition available. + Details
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