Additional Interest

No definition available.

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- Definition

Interest Rate On Notes Payable To Bank

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Line Of Credit Facility Borrowing Base

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line of Credit Facility Borrowing Base Percentage of Accounts Receivable

+ References

No definition available.

+ Details

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- Definition

Line of Credit Facility Borrowing Base Percentage of Eligible Inventory

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

States whether the entity was in compliance with the debt covenants throughout the reporting period, and describes facts and circumstances of any compliance failure.

+ 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 942

-SubTopic 470

-Section 50

-Paragraph 3

-Subparagraph (g)

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

+ Details

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- Definition

Identification of the lender and information about a contractual promise to repay a short-term or long-term obligation, which includes borrowings under lines of credit, notes payable, commercial paper, bonds payable, debentures, and other contractual obligations for payment. This may include rationale for entering into the arrangement, significant terms of the arrangement, which may include amount, repayment terms, priority, collateral required, debt covenants, borrowing capacity, call features, participation rights, conversion provisions, sinking-fund requirements, voting rights, basis for conversion if convertible and remarketing provisions. The description may be provided for individual debt instruments, rational groupings of debt instruments, or by debt in total.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644

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)

-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, 20, 22

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

-Section 50

-Paragraph 3

-Subparagraph (a)

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

+ Details

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20, 22

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

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

- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

+ 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))

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

Reference 2: 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:	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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

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- Details

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- Details

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- Details

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- Details

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Long Term Obligations - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Nov. 13, 2014	Mar. 13, 2015
Schedule of Capitalization, Long-term Debt [Line Items]
Debt instrument description	The secured notes payable to bank evidence borrowings under a revolving credit facility which permits us to borrow up to the lesser of (i) $25,000,000, or (ii) an amount equal to 85% of the value of our eligible accounts receivable and up to 55% of the value of our eligible inventory.
Debt instrument covenant compliance	As of December 31, 2014, we were in compliance with all of our financial and other covenants under our line of credit agreement.
Line of credit borrowing capacity	$ 25,000,000
Percentage of eligible accounts receivable permitted to borrow under the line of credit	85.00%
Percentage of eligible inventories permitted to borrow under the line of credit	55.00%
Borrowing base of the company	17,000,000crv_LineOfCreditFacilityBorrowingBase	13,800,000crv_LineOfCreditFacilityBorrowingBase
Credit facility maturity date	Jul. 10, 2017
19th Amendment
Schedule of Capitalization, Long-term Debt [Line Items]
Percentage of eligible accounts receivable permitted to borrow under the line of credit			85.00%
19th Amendment \| Minimum
Schedule of Capitalization, Long-term Debt [Line Items]
Percentage of eligible inventories permitted to borrow under the line of credit			50.00%
19th Amendment \| Maximum
Schedule of Capitalization, Long-term Debt [Line Items]
Percentage of eligible inventories permitted to borrow under the line of credit			55.00%
19th Amendment \| During the months of February and July 2015
Schedule of Capitalization, Long-term Debt [Line Items]
Line of credit borrowing capacity			27,000,000
19th Amendment \| During the months of March, April and May 2015
Schedule of Capitalization, Long-term Debt [Line Items]
Line of credit borrowing capacity			30,000,000
19th Amendment \| During the month of June 2015
Schedule of Capitalization, Long-term Debt [Line Items]
Line of credit borrowing capacity			29,000,000
19th Amendment \| For the months of January, August, September, October, November and December 2015
Schedule of Capitalization, Long-term Debt [Line Items]
Line of credit borrowing capacity			25,000,000
Subsequent Event
Schedule of Capitalization, Long-term Debt [Line Items]
Outstanding borrowings under revolving credit facility				$ 18,390,000
Prime Rate
Schedule of Capitalization, Long-term Debt [Line Items]
Interest rate payable	3.25%
Additional rate of interest	1.75%
LIBOR Rate
Schedule of Capitalization, Long-term Debt [Line Items]
Interest rate payable	0.25%
Additional rate of interest	3.25%