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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details 2) (USD $) In Thousands, unless otherwise specified | 12 Months Ended | 1 Months Ended | 12 Months Ended
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Dec. 28, 2013 | Dec. 29, 2012 | Dec. 31, 2011 | Nov. 30, 2013 Delta EMD, Ltd. | Dec. 28, 2013 Buildings and improvements Minimum | Dec. 28, 2013 Buildings and improvements Maximum | Dec. 28, 2013 Machinery and equipment Minimum | Dec. 28, 2013 Machinery and equipment Maximum | Dec. 28, 2013 Transportation equipment Minimum | Dec. 28, 2013 Transportation equipment Maximum | Dec. 28, 2013 Office furniture and equipment Minimum | Dec. 28, 2013 Office furniture and equipment Maximum
Long-lived assets |  |  |  |  |  |  |  |  |  |  |  |
Estimated useful lives |  |  |  |  | 15 years | 40 years | 3 years | 12 years | 3 years | 24 years | 3 years | 7 years
Depreciation expense | $ 62,291 | $ 55,559 | $ 54,352 |  |  |  |  |  |  |  |  |
Impairment loss | $ 12,161 |  |  | $ 12,161 |  |  |  |  |  |  |  |

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- Definition The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585 + Details
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- Details
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- Definition Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment. + References No definition available. + Details
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- Definition Represents the amount of charge against earnings in the period to reduce the carrying amount of property, plant and equipment. + References No definition available. + Details
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