Inventoried Costs (Details) - USD ($) $ in Millions	Jun. 26, 2016	Dec. 27, 2015
Inventory Disclosure [Abstract]
Raw materials	$ 29.9	$ 32.9
Work in process	23.8	19.2
Finished goods	1.2	2.6
Supplies and other	1.6	1.6
Subtotal inventoried costs	56.5	56.3
Less: Customer advances and progress payments	(6.6)	(0.7)
Total inventoried costs	$ 49.9	$ 55.6

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

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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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Carrying amount (lower of cost or market) of inventories less all valuation, other allowances, and progress payments or customer advances received on long-term contracts or programs. Excludes noncurrent inventory balances (expected to remain on hand past one year or one operating cycle, if longer).

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of unprocessed items to be consumed in the manufacturing or production process.

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Carrying amount, net of reserves and adjustments, as of the balance sheet date of merchandise or goods which are partially completed. This inventory is generally comprised of raw materials, labor and factory overhead costs, which require further materials, labor and overhead to be converted into finished goods, and which generally require the use of estimates to determine percentage complete and pricing.

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Carrying amount, net of valuation reserves and allowances, as of the balance sheet date of inventories not otherwise specified in the taxonomy.

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Amount of advances received from customers under long-term contracts which have been offset against inventories accounts at the balance sheet date.

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