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Inventory for Long-term Contracts or Programs, Costs Incurred on Uncompleted Contracts

No definition available.

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Inventory for Long-term Contracts or Programs, Estimated Earnings on Uncompleted Contracts

No definition available.

Name:	orn_InventoryForLongTermContractsOrProgramsEstimatedEarningsOnUncompletedContracts
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Total amounts billed for services rendered or to be rendered on uncompleted customer contracts.

No definition available.

Name:	orn_TotalBillingsOnUncompletedContracts
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Data Type:	xbrli:monetaryItemType
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Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
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-URI https://asc.fasb.org/extlink&oid=126919976&loc=SL49130531-203044

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=126919976&loc=SL49130531-203044

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- References

No definition available.

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Data Type:	xbrli:stringItemType
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Period Type:	duration

Amount before valuation and LIFO reserves, and progress payments, of inventory associated with long-term contracts, expected to be sold, or consumed within one year or operating cycle, if longer.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(6)(a)(2))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682