balance outstanding under revolver

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- Definition

Fixed Charge Coverage Ratio

+ References

No definition available.

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- Definition

Leverage Ratio

+ References

No definition available.

+ Details

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- Definition

Line of Credit, Current Borrowing Capacity Base Components

+ References

No definition available.

+ Details

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- Definition

Line of Credit Facility, Additional Borrowing Capacity

+ References

No definition available.

+ Details

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- Definition

Line of Credit Facility, Integral Multiple of Borrowings

+ References

No definition available.

+ Details

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- Definition

Line of Credit Facility, Revolving Credit Converted to Term Loan, Amount Outstanding

+ References

No definition available.

+ Details

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- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

+ Details

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=6584090&loc=d3e28878-108400

+ Details

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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- Details

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- Definition

Amount of the required periodic payments including both interest and principal payments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

-Section 50

-Paragraph 3

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of the required periodic payments applied to principal.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

Name:	us-gaap_LettersOfCreditOutstandingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The effective interest rate at the end of the reporting period.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The effective interest rate during the reporting period.

+ References

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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- Definition

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(f))

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph f

-Article 4

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

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-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 14

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3255-108585

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Balance Type:	debit
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- Details

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- Details

Name:	orn_CreditFacilityNameAxis=orn_AmendedCreditAgreementOf2012Member
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Long-term Debt and Line of Credit (Details) (USD $)	1 Months Ended		12 Months Ended			1 Months Ended
Long-term Debt and Line of Credit (Details) (USD $)	Sep. 30, 2014	Feb. 28, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2014
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity			$ 7,900,000			$ 7,900,000
balance outstanding under revolver			26,000,000orn_Balanceoutstandingunderrevolver			26,000,000orn_Balanceoutstandingunderrevolver
Proceeds from credit facility	3,500,000us-gaap_ProceedsFromLinesOfCredit	22,500,000us-gaap_ProceedsFromLinesOfCredit	30,000,000us-gaap_ProceedsFromLinesOfCredit	0us-gaap_ProceedsFromLinesOfCredit	18,000,000us-gaap_ProceedsFromLinesOfCredit
Fixed Charge Coverage Ratio			1.50orn_FixedChargeCoverageRatio
Leverage Ratio			2.50orn_LeverageRatio
Debt instrument, description of variable rate basis			LIBOR
Line of credit facility, interest rate during period			2.19%
LIBOR
Debt Instrument [Line Items]
Line of credit facility, interest rate at period end			2.1875%			2.1875%
Secured debt
Debt Instrument [Line Items]
Line of credit facility, additional borrowing capacity			25,000,000			25,000,000
Line of credit facility, revolving credit converted to term loan, amount outstanding			11,000,000			11,000,000
Line of credit facility, unused capacity commitment fee percentage			0.25%
Secured debt \| Term Loan One [Member]
Debt Instrument [Line Items]
Debt instrument, periodic payment, principal			389,000
Debt Instrument, Interest Rate, Stated Percentage			3.10%			3.10%
Secured debt \| Term Loan Two [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount			4,000,000			4,000,000
Debt Instrument, Periodic Payment						53,000
Letter of credit \| Secured debt
Debt Instrument [Line Items]
Line of credit facility, current borrowing capacity			20,000,000			20,000,000
Letters of credit outstanding, amount			1,100,000			1,100,000
Prime rate based Loans \| Revolving Line of Credit [Member] \| Secured debt
Debt Instrument [Line Items]
Line of credit facility, integral multiple of borrowings			500,000
Prime rate based Loans \| Swingline loan \| Secured debt
Debt Instrument [Line Items]
Line of credit facility, integral multiple of borrowings			100,000
Eurodollar Loans \| Revolving Line of Credit [Member] \| Secured debt
Debt Instrument [Line Items]
Line of credit facility, integral multiple of borrowings			1,000,000
Eligible accounts receivable
Debt Instrument [Line Items]
Line of credit, current borrowing capacity base components			80.00%
Adjusted cash balance
Debt Instrument [Line Items]
Line of credit, current borrowing capacity base components			90.00%
Amended credit agreement
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity			$ 35,000,000			$ 35,000,000