Business Combinations (Details) $ in Thousands	1 Months Ended	6 Months Ended	12 Months Ended
Aug. 06, 2019 USD ($)	Jun. 29, 2019 USD ($)	Jun. 30, 2018 USD ($)	Dec. 31, 2018 USD ($)
Investment in businesses		$ 4,480	$ 3,534
Liabilities assumed		314		$ 2,381
Debt issued for purchases of businesses		1,133	990	2,402
Payments to Acquire Businesses, Gross		3,033		8,461
Cash		3		0
Receivables		41		1,311
Operating supplies		79		23
Prepaid expense		13		89
Equipment		830		4,079
Deposits and other		0		7
Intangibles		2,135		4,895
Goodwill		$ 1,379	$ 1,013	$ 2,840
Subsequent event [Member]
Investment in businesses	$ 932
Liabilities assumed	0
Debt issued for purchases of businesses	$ 157
Number of Businesses Acquired	2
Customer lists [Member]
Finite-Lived Intangible Asset, Useful Life		6 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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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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The amount of inventory recognized as of 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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The number of businesses acquired by the entity during the period.

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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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