Cover Page - USD ($) $ in Thousands, shares in Millions	12 Months Ended
	Dec. 31, 2021	Mar. 28, 2022	Jun. 30, 2021
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Transition Report	false
Document Period End Date	Dec. 31, 2021
Entity File Number	333-253583
Entity Registrant Name	Leonardo DRS, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	13-2632319
Entity Address, Address Line One	2345 Crystal Drive
Entity Address, Address Line Two	Suite 1000
Entity Address, City or Town	Arlington
Entity Address, State or Province	VA
Entity Address, Postal Zip Code	22202
City Area Code	703
Local Phone Number	416-8000
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	false
Entity Shell Company	false
Entity Public Float			$ 0
Entity Common Stock, Shares Outstanding		145
Amendment Flag	false
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	FY
Entity Central Index Key	0001833756
Current Fiscal Year End Date	--12-31