Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 64,928	$ 59,632
Accounts receivable, net	31,625	32,286
Inventory	49,212	46,845
Prepaid expenses and other current assets	7,609	6,136
Total current assets	153,374	144,899
Property and equipment, net	60,262	61,561
Field equipment, net	24,264	22,309
Deferred cost of revenues, net	31,410	33,165
Intangible assets, net	7,660	9,688
Goodwill	42,748	42,648
Other assets	5,911	2,937
Total assets	325,629	317,207
Current liabilities:
Accounts payable	14,785	14,177
Accrued expenses	27,985	30,985
Current portion of long-term debt	101	328
Other current liabilities	4,559	3,770
Total current liabilities	47,430	49,260
Deferred revenues	46,874	49,001
Long-term debt	520	1,305
Other long-term liabilities	17,824	15,568
Total liabilities	112,648	115,134
Commitments and contingencies (Note 10)
Noncontrolling interests subject to put provisions	(165)	50
Stockholders’ equity:
Undesignated preferred stock: par value $0.001 per share, 5,000,000 shares authorized; no shares issued and outstanding as of December 31, 2017 and 2016	0	0
Common stock: par value $0.001 per share, 100,000,000 shares authorized; 67,341,819 and 65,883,026 shares issued as of December 31, 2017 and 2016, respectively	67	65
Additional paid-in capital	657,640	631,219
Accumulated deficit	(421,593)	(407,601)
Accumulated other comprehensive loss	(3,673)	(6,101)
Treasury stock, at cost: 1,046,870 and 936,360 shares as of December 31, 2017 and 2016, respectively	(19,283)	(16,184)
Total NxStage Medical, Inc. stockholders’ equity	213,158	201,398
Noncontrolling interests not subject to put provisions	(12)	625
Total stockholders’ equity	213,146	202,023
Total liabilities and stockholders’ equity	$ 325,629	$ 317,207

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.