Credit Facility (Details) (USD $)	3 Months Ended
Mar. 31, 2013
Credit Facility (Textual) [Abstract]
Term agreement of senior secured credit facility	3 years
Amount of senior secured credit facility	$ 25,000,000
Percentage of eligible account receivable	80.00%
Percentage of domestically held raw material and finished goods inventory	35.00%
Percentage of advances against inventory	40.00%
Amount of aggregate outstanding on the revolving line of credit	10,000,000
Option to borrow at an interest rate of LIBOR plus	2.75%
Option to borrow at an interest rate of Wall Street Journal prime rate plus	0.50%
Liquidity rate	20,000,000
Borrowing interest rate options	2.25%
Percentage of unused revolving line facility fee	0.375%
Adjusted quick ratio	1.40%
Percentage of maintain operating and other deposit accounts	25.00%
Interest expense charged on the unused portion of the facility	$ 23,000

Adjusted quick ratio.

No definition available.

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- Details

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- Definition

Line of credit facility agreement period.

+ References

No definition available.

+ Details

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- Definition

Line of credit facility basis spread on London inter bank offered rate.

+ References

No definition available.

+ Details

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- Definition

Line of credit facility basis spread on prime rate.

+ References

No definition available.

+ Details

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- Definition

Line of credit facility liquidity maintained basis spread on London inter bank offered rate.

+ References

No definition available.

+ Details

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- Definition

Line of credit facility maximum borrowing capacity as percentage of accounts receivable.

+ References

No definition available.

+ Details

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Namespace Prefix:	rbcn_
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Period Type:	duration

- Definition

Line of credit facility maximum borrowing capacity as percentage of raw material and finished goods inventory.

+ References

No definition available.

+ Details

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- Definition

Line of credit facility outstanding maximum amount of advances against inventory.

+ References

No definition available.

+ Details

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Namespace Prefix:	rbcn_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Percentage of advances against inventory.

+ References

No definition available.

+ Details

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- Definition

Maximum liquidity amount with lending institution.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Percentage of cash securities and investments maintained for deposit accounts.

+ References

No definition available.

+ Details

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- Definition

The cost of borrowed funds accounted for as interest that was charged against earnings during the period.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 9

-Article 9

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

-Publisher OTS

-Name Federal Regulation (FR)

-Number Title 12

-Section 563c.102

-Paragraph 9

-Chapter V

-Subsection II

-LegacyDoc This is a non-GAAP reference that was included in the 2009 taxonomy. It will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 34

-Paragraph 21

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.9)

-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

+ Details

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Balance Type:	debit
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- 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

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 2, 4

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

+ Details

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Balance Type:	credit
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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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