Inventories - Schedule of Inventory (Details) - USD ($) $ in Thousands	Mar. 29, 2019	Dec. 31, 2018
Inventory Disclosure [Abstract]
Merchandise for resale	$ 163,330	$ 162,985
Raw materials	15,438	15,939
Contracts and other work in process (including certain general stock materials)	112,477	97,025
Finished goods	22,649	18,963
Total	$ 313,894	$ 294,912

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Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount before valuation and LIFO reserves of raw materials expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount before valuation and LIFO reserves of merchandise or goods in the production process expected to be completed within one year or operating cycle, if longer.

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Carrying amount as of the balance sheet date of merchandise inventory purchased by a retailer, wholesaler or distributor and held for future sale.

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