Business Combinations (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 30, 2019	Mar. 31, 2018	Dec. 31, 2018
Investment in businesses	$ 4,056	$ 86
Liabilities assumed	245		$ 2,381
Debt issued for purchases of businesses	895	0	2,402
Cash paid	2,916		8,461
Receivables	41		1,311
Operating supplies	79		23
Prepaid expense	13		89
Equipment	830		4,079
Intangibles	1,861		4,895
Goodwill	$ 1,232	$ 0	$ 2,840
Customer lists [Member]
Finite-Lived Intangible Asset, Useful Life	7 years
Noncompete Agreements [Member]
Finite-Lived Intangible Asset, Useful Life	5 years

Fair value of acquired receivable from business combination, excluding certain loans and debt securities acquired in transfer.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of liabilities incurred by the acquirer as part of consideration transferred in a business combination.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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- Definition

Amount of tangible personal property used to produce goods and services, including, but is not limited to, tools, dies and molds, computer and office equipment, acquired at the acquisition date.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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The amount of inventory recognized as of the acquisition date.

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Amount of liabilities assumed at the acquisition date.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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