CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014		Sep. 30, 2013
Income Statement [Abstract]
Net sales	$ 268,297		$ 216,898		$ 763,425		$ 631,796
Cost of sales	173,335		144,559		494,784		425,949
Gross profit	94,962		72,339		268,641		205,847
Selling, general, and administrative expenses	71,647		55,288		211,102		166,094
Restructuring charges	0		0		203		0
Operating profit	23,315	[1]	17,051	[1]	57,336	[1]	39,753	[1]
Interest expense	1,899		1,484		5,514		4,496
Other (income) expense, net	(3,294)		2,224		(3,098)		(1,273)
Income before income tax expense	24,710		13,343		54,920		36,530
Income tax expense	9,088		4,793		20,266		14,018
Net earnings	15,622		8,550		34,654		22,512
Net earnings (loss) attributable to noncontrolling interests	(31)		0		(39)		0
Net earnings attributable to Knoll, Inc. stockholders	15,653		8,550		34,693		22,512
Net earnings per common share attributable to Knoll, Inc. stockholders:
Basic (in dollars per share)	$ 0.33		$ 0.18		$ 0.73		$ 0.48
Diluted (in dollars per share)	$ 0.33		$ 0.18		$ 0.72		$ 0.47
Dividends per share (in dollars per share)	$ 0.12		$ 0.12		$ 0.36		$ 0.36
Weighted-average number of common shares outstanding:
Basic (in shares)	47,376,605		46,915,660		47,314,810		46,882,362
Diluted (in shares)	48,072,632		47,679,422		48,032,710		47,615,305
Net earnings	15,622		8,550		34,654		22,512
Other comprehensive income (loss):
Foreign currency translation adjustment	(7,488)		4,047		(7,577)		(3,164)
Pension and other post retirement liability adjustment, net of tax	64		913		191		2,782
Total other comprehensive income (loss), net of tax	(7,424)		4,960		(7,386)		(382)
Total comprehensive income	8,198		13,510		27,268		22,130
Comprehensive earnings (loss) attributable to noncontrolling interests	(31)		0		(39)		0
Comprehensive income attributable to Knoll, Inc. stockholders	$ 8,229		$ 13,510		$ 27,307		$ 22,130

[1] The Company does not allocate interest expense or other (income) expense, net to the reportable segments.