BORROWINGS, Contractual Maturity on Borrowings (Details) - USD ($) $ in Thousands	12 Months Ended
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%

The average effective interest rate during the reporting period.

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

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