Sale of Energy Systems Division (Details) (USD $) In Millions, unless otherwise specified	0 Months Ended	12 Months Ended
Oct. 01, 2009	Dec. 31, 2012
Sale of Energy Systems Division (Details) [Line Items]
Divestiture Cost of Significant Assets Sold Sale Price	$ 10.0
Proceeds from Divestiture of Businesses	8.6
Divestiture Contingent Consideration Potential Consideration Receivable	1.4
Divestiture Contingent Consideration Potential Consideration Receivable Cancelled	0.5
Gain (Loss) Related to Litigation Settlement		0.3
Contingent Upon Applied Utility Systems [Member]
Sale of Energy Systems Division (Details) [Line Items]
Divestiture Contingent Consideration Potential Consideration Receivable	0.5
Retention of Certain Project And Contract Warranties And Other Obligation [Member]
Sale of Energy Systems Division (Details) [Line Items]
Divestiture Contingent Consideration Potential Consideration Receivable	$ 0.9

Amount of potential cash receipts that could result from the contingent consideration arrangement.

No definition available.

Name:	cdti_DivestitureContingentConsiderationPotentialConsiderationReceivable
Namespace Prefix:	cdti_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of potential cash receipts that could result from the contingent consideration arrangement cancelled.

+ References

No definition available.

+ Details

Name:	cdti_DivestitureContingentConsiderationPotentialConsiderationReceivableCancelled
Namespace Prefix:	cdti_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The total consideration determined for the significant assets of a business division sold.

+ References

No definition available.

+ Details

Name:	cdti_DivestitureCostOfSignificantAssetsSoldSalePrice
Namespace Prefix:	cdti_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	cdti_SaleofEnergySystemsDivisionDetailsLineItems
Namespace Prefix:	cdti_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of gain (loss) recognized in settlement of litigation and insurance claims. Excludes claims within an insurance entity's normal claims settlement process.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

+ Details

Name:	us-gaap_GainLossRelatedToLitigationSettlement
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 12

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3179-108585

+ Details

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