FAIR VALUE MEASUREMENT (Details) - USD ($) $ in Thousands	Oct. 01, 2017	Jan. 01, 2017
Fair Value Measurement [Line Items]
Other restricted assets	$ 21,115	$ 16,925
Restricted investments classified as held-to-maturity	165,053	145,953
Contingent consideration	0	21,600
Total Fair Value
Fair Value Measurement [Line Items]
Cash and cash equivalents	35,055	34,970
Total Fair Value \| Restricted Assets
Fair Value Measurement [Line Items]
Restricted cash and cash equivalents	59,788	67,751
Other restricted assets	21,115	16,925
Restricted investments classified as held-to-maturity	165,053	145,953
Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value Measurement [Line Items]
Cash and cash equivalents	35,055	34,970
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Restricted Assets
Fair Value Measurement [Line Items]
Restricted cash and cash equivalents	59,788	67,751
Other restricted assets	21,115	16,925
Restricted investments classified as held-to-maturity	0	0
Significant Other Observable Inputs (Level 2)
Fair Value Measurement [Line Items]
Cash and cash equivalents	0	0
Significant Other Observable Inputs (Level 2) \| Restricted Assets
Fair Value Measurement [Line Items]
Restricted cash and cash equivalents	0	0
Other restricted assets	0	0
Restricted investments classified as held-to-maturity	165,053	145,953
Significant Unobservable Inputs (Level 3)
Fair Value Measurement [Line Items]
Cash and cash equivalents	0	0
Significant Unobservable Inputs (Level 3) \| Restricted Assets
Fair Value Measurement [Line Items]
Restricted cash and cash equivalents	0	0
Other restricted assets	0	0
Restricted investments classified as held-to-maturity	$ 0	0
SIMOS Insourcing Solutions Corporation \| Total Fair Value
Fair Value Measurement [Line Items]
Contingent consideration		21,600
SIMOS Insourcing Solutions Corporation \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value Measurement [Line Items]
Contingent consideration		0
SIMOS Insourcing Solutions Corporation \| Significant Other Observable Inputs (Level 2)
Fair Value Measurement [Line Items]
Contingent consideration		0
SIMOS Insourcing Solutions Corporation \| Significant Unobservable Inputs (Level 3)
Fair Value Measurement [Line Items]
Contingent consideration		$ 21,600

Amount of liability recognized arising from contingent consideration in a business combination.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Fair value of investments in debt securities classified as held-to-maturity.

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Amount of noncurrent assets that are pledged or subject to withdrawal restrictions, classified as other.

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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