Segment Information - Schedule Of Segment Reporting (Detail) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2025	Mar. 31, 2024
Segment Reporting Information [Line Items]
Collaboration revenue		$ 16,627	$ 28,935
Type of Revenue [Extensible List]		us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember
Research and development		$ 108,427	$ 111,847
General and administrative		29,007	31,091
Interest income		(8,603)	(12,632)
Net loss		(114,329)	(107,436)
Operating Segments [Member]
Segment Reporting Information [Line Items]
Collaboration revenue		$ 16,627	$ 28,935
Type of Revenue [Extensible List]		us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember
Research and development		$ 108,427	$ 111,847
General and administrative	[1]	29,007	31,091
Interest income		(8,603)	(12,632)
Other segment information	[2]	2,125	6,065
Net loss		(114,329)	(107,436)
Nex-z [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Research and development		23,130	13,658
NTLA-2002 [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Research and development		10,668	8,793
Other Research And Development [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Research and development	[3]	$ 74,629	$ 89,396

[1] Includes stock-based compensation of $9.2 million and $14.0 million for the three months ended March 31, 2025 and 2024, respectively, as disclosed within Note 10, “Stock-Based Compensation.”

[2] Includes change in fair value of investments as disclosed on the Company’s condensed consolidated statements of operations and comprehensive loss.

[3] Includes unallocated research and development expenses including stock-based compensation of $12.6 million and $20.1 million for the three months ended March 31, 2025 and 2024, respectively, as disclosed within Note 10, “Stock-Based Compensation.”