Collaboration Agreements - Additional Information (Detail) $ / shares in Units, $ in Thousands, shares in Millions	1 Months Ended		7 Months Ended	12 Months Ended			34 Months Ended
	Feb. 28, 2018 USD ($)	Aug. 31, 2017 USD ($) employee $ / shares shares	Dec. 31, 2015 USD ($)	Dec. 31, 2019 USD ($) $ / shares	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Jan. 31, 2020 shares
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration				$ 125,568	$ 106,732	$ 114,905
Exercise Price Of Common Stock Warrants | $ / shares				$ 19.47
Celgene Corporation | Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestone payments	$ 19,000
Proceeds from Collaborators				$ 1,100	600	600
Collaboration				4,400	2,600	200
Celgene Corporation | Collaborative Arrangement | Upfront Payment Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration agreement upfront payment	5,800						$ 2,100
Celgene Corporation | Collaborative Arrangement | Maximum
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestone payments	$ 24,800
Merck Sharp & Dohme Corp. | Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration					1,600	27,000
Merck Sharp & Dohme Corp. | Collaborative Arrangement | Upfront Payment Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Proceeds from Collaborators			$ 3,900			12,000
Collaboration						8,500
Merck Sharp & Dohme Corp. | Collaborative Arrangement | Development Funding
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Proceeds from Collaborators					1,100	6,800
Medivation, Inc. and Astellas Pharma, Inc. | Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Proceeds from Collaborators						900
Collaboration						11,500
Lam Research Corporation | Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Proceeds from Collaborators				14,900	21,700	13,400
Collaboration				16,300	$ 18,600	$ 3,700
Maximum Amount Of Royalties Payable, Ratio To License And Service Revenue		3
Reimbursement Of Counterparty Costs, Maximum Number Of Employees | employee		10
Exercise Price Of Common Stock Warrants | $ / shares		$ 16.75
Stock and Warrants Issued During Period, Value, Preferred Stock and Warrants		$ 6,700
Other Liabilities, Current				5,500
nstg_ReimbursementOfCounterpartyCosts				$ 800
Lam Research Corporation | Collaborative Arrangement | Maximum
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration		$ 50,000
Class of Warrant or Right, Outstanding | shares		1.0
Subsequent Event | Lam Research Corporation | Collaborative Arrangement | Maximum
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Class of Warrant or Right, Outstanding | shares								0.4