CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Income Statement [Abstract]
Sales	$ 294,700	$ 268,622	$ 579,329	$ 535,120
Cost of sales	180,636	167,431	357,501	338,620
Gross profit	114,064	101,191	221,828	196,500
Selling, general, and administrative expenses	80,590	72,936	156,505	145,946
Operating profit	33,474	28,255	65,323	50,554
Interest expense	1,307	1,851	2,861	3,736
Other expense (income), net	185	200	2,789	(6,957)
Income before income tax expense	31,982	26,204	59,673	53,775
Income tax expense	10,678	8,982	21,100	19,118
Net earnings	21,304	17,222	38,573	34,657
Net earnings (loss) attributable to noncontrolling interests	6	(17)	17	(25)
Net earnings attributable to Knoll, Inc. stockholders	$ 21,298	$ 17,239	$ 38,556	$ 34,682
Net earnings per common share attributable to Knoll, Inc. stockholders:
Basic (in dollars per share)	$ 0.44	$ 0.36	$ 0.80	$ 0.73
Diluted (in dollars per share)	0.44	0.36	0.79	0.72
Dividends per share (in dollars per share)	$ 0.15	$ 0.12	$ 0.30	$ 0.24
Weighted-average number of common shares outstanding:
Basic (in shares)	48,018,733	47,760,961	47,961,661	47,705,222
Diluted (in shares)	48,664,318	48,509,546	48,588,725	48,445,060
Other comprehensive income (loss):
Pension and other postretirement liability adjustment, net of tax	$ (136)	$ 1,382	$ (272)	$ 2,764
Foreign currency translation adjustment	1,566	118	5,616	(12,881)
Total other comprehensive income (loss), net of tax	1,430	1,500	5,344	(10,117)
Total comprehensive income	22,734	18,722	43,917	24,540
Comprehensive income (loss) attributable to noncontrolling interests	6	(17)	17	(25)
Comprehensive income attributable to Knoll, Inc. stockholders	$ 22,728	$ 18,739	$ 43,900	$ 24,565