ACQUISITION - Net Sales and Earnings of Acquiree Included in Consolidated Results (Details) (USD $)	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Feb. 03, 2014
Business Acquisition [Line Items]
Contingent purchase price payment	$ (5,000,000)	$ 0
Holly Hunt Enterprises, Inc [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Less Noncontrolling Interest			95,000,000
Business Combination, Contingent Consideration, Liability			16,000,000
Contingent purchase price payment	5,000,000
Net Sales and Earnings of Acquiree Included in Consolidated Results [Abstract]
Net sales	25,891,000	17,360,000
Net earnings attributable to Knoll, Inc. stockholders	$ 470,000	$ 1,106,000

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- Definition

Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

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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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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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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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