Customer Contracts (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Jun. 30, 2017
Gross and net amount of uncompleted contracts
Costs and estimated earnings recognized on uncompleted contracts	$ 2,081,799	$ 1,919,054
Billings on uncompleted contracts	2,125,907	1,903,001
Total	(44,108)	16,053
Shown on balance sheet as:
Costs and estimated earnings in excess of billings on uncompleted contracts	76,632	91,180
Billings on uncompleted contracts in excess of costs and estimated earnings	120,740	75,127
Total	$ (44,108)	$ 16,053

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Uncompleted contracts billings.

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Uncompleted contracts costs incurred and estimated earnings recognized.

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Uncompleted contracts.

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Liability attributable to (i) billings in excess of costs under the percentage of completion contract accounting method representing the difference between contractually invoiced amounts (billings) and revenue recognized based, for example, on costs incurred to estimated total costs at period end or (ii) contractually invoiced amounts (billings) in excess of costs incurred and accumulated under the completed contract accounting method.

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Amount of receivable reflecting the cost incurred on uncompleted contracts in excess of related billings.

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Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
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Amount of receivable reflecting the cost incurred on uncompleted contracts in excess of related billings which is expected to be collected within one year or the normal operating cycle, if longer.

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