Condensed Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Statement of Comprehensive Income [Abstract]
Revenues	$ 107,298	$ 96,829
Cost of revenues	61,133	55,639
Gross profit	46,165	41,190
Operating expenses:
Selling and marketing	18,055	16,770
Research and development	9,438	9,508
Distribution	9,342	7,643
General and administrative	10,460	8,950
Total operating expenses	47,295	42,871
Loss from operations	(1,130)	(1,681)
Other expense:
Interest expense, net	(109)	(203)
Other expense, net	(295)	(270)
Total other expense	(404)	(473)
Net loss before income taxes	(1,534)	(2,154)
Provision for (benefit from) income taxes	264	(613)
Net loss	(1,798)	(1,541)
Less: Net loss attributable to noncontrolling interests	(339)	(352)
Net loss attributable to NxStage Medical, Inc.	$ (1,459)	$ (1,189)
Net loss per share, basic and diluted (in dollars per share)	$ (0.02)	$ (0.02)
Weighted-average shares outstanding, basic and diluted (in shares)	66,355	65,275
Other comprehensive income:
Unrealized income on derivative instruments, net of income taxes	$ 461	$ 2,184
Other income	698	721
Total other comprehensive income	1,159	2,905
Total comprehensive (loss) income	(639)	1,364
Less: Comprehensive loss attributable to noncontrolling interests	(339)	(352)
Total comprehensive (loss) income attributable to NxStage Medical, Inc.	$ (300)	$ 1,716