ACQUISITIONS - Net Sales and Earnings of Acquiree Included in Consolidated Results (Details) (Holly Hunt Enterprises, Inc [Member], USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2014	Sep. 30, 2014	Feb. 03, 2014
Holly Hunt Enterprises, Inc [Member]
Business Acquisition [Line Items]
Purchase Price			$ 95,000
Business Combination, Contingent Consideration, Liability			16,000
Net Sales and Earnings of Acquiree Included in Consolidated Results [Abstract]
Net sales	29,495	74,004
Net earnings attributable to Knoll, Inc. stockholders	$ 1,725	$ 4,833

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- Definition

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

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- Definition

This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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- Definition

This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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- Definition

Amount recognized as of the acquisition date for the assets, including goodwill, in excess of (less than) the aggregate liabilities assumed, less the noncontrolling interest in the acquiree.

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