cm:Concept: us-gaap:BusinessCombinationStepAcquisitionEquityInterestInAcquireeValuationTechniques
| Business Combination, Step Acquisition, Equity Interest in Acquiree, Valuation Techniques |
| us-gaap:BusinessCombinationStepAcquisitionEquityInterestInAcquireeValuationTechniques |
| In a business combination achieved in stages, description of the valuation technique(s) used to measure the acquisition date fair value of the equity interest in the acquiree held by the acquirer immediately before the business combination and information that enables users of the acquirer's financial statements to assess the inputs used to develop the fair value measurement of the equity interest in the acquiree held by the acquirer immediately before the business combination. |
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| us-gaap:BusinessCombinationStepAcquisitionEquityInterestInAcquireeValuationTechniques |