CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Statement [Abstract]
Sales	$ 1,104,442	$ 1,050,294	$ 862,252
Cost of sales	692,310	678,609	581,920
Gross profit	412,132	371,685	280,332
Selling, general, and administrative expenses	299,476	286,801	224,915
Restructuring and other charges	896	1,532	5,104
Intangible asset impairment charges	10,650	0	8,900
Pension settlement and OPEB curtailment	0	6,509	0
Operating profit	101,110	76,843	41,413
Interest expense	6,865	7,378	5,941
Other income, net	(9,174)	(6,285)	(3,430)
Income before income tax expense	103,419	75,750	38,902
Income tax expense	37,471	29,165	15,718
Net earnings	65,948	46,585	23,184
Net loss attributable to noncontrolling interests	(15)	(11)	0
Net earnings attributable to Knoll, Inc. stockholders	$ 65,963	$ 46,596	$ 23,184
Net earnings per common share attributable to Knoll, Inc. stockholders:
Basic (in dollars per share)	$ 1.38	$ 0.98	$ 0.49
Diluted (in dollars per share)	$ 1.36	$ 0.97	$ 0.49
Weighted-average number of common shares outstanding:
Basic (in shares)	47,746,707	47,346,532	46,916,845
Diluted (in shares)	48,438,231	48,068,249	47,659,418
Other comprehensive income (loss):
Pension and other postretirement liability adjustment, net of tax	$ 11,945	$ (25,548)	$ 36,729
Foreign currency translation adjustment	(16,581)	(12,271)	(4,814)
Total other comprehensive income (loss), net of tax	(4,636)	(37,819)	31,915
Comprehensive income attributable to Knoll, Inc. stockholders	61,312	8,766	55,099
Comprehensive loss attributable to noncontrolling interests	(15)	(11)	0
Comprehensive income attributable to Knoll, Inc. stockholders	$ 61,327	$ 8,777	$ 55,099