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Represents the remaining number of shares which are to be issued to certain officers in lieu of cash payments.

No definition available.

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Represents the number of shares issuable to certain officers in lieu of cash payments.

No definition available.

Name:	cldx_BusinessAcquisitionStockIssuableInLieuOfSeverance
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Represents the number of shares issued to certain officers in lieu of cash payments

No definition available.

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Number of shares of equity interests issued or issuable to acquire entity.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

Name:	us-gaap_BusinessAcquisitionLineItems
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This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=73531572&loc=d3e1043-128460

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- References

No definition available.

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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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This element represents the amount of any change recognized during the period in the high-end of the estimated range of outcomes (undiscounted) of a liability assumed in a business combination arising from an item of contingent consideration.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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This element represents the amount of any change recognized during the period in the low-end of the estimated range of outcomes (undiscounted) of a liability assumed in a business combination arising from an item of contingent consideration.

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Amount of liability recognized arising from contingent consideration in a business combination.

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Amount of liability recognized arising from contingent consideration in a business combination, expected to be settled beyond one year or the normal operating cycle, if longer.

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-Publisher FASB
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Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Data Type:	num:percentItemType
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Period Type:	duration

Price of a single share of a number of saleable stocks of a company.

No definition available.

Name:	us-gaap_SharePrice
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

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