Document And Entity Information - shares	9 Months Ended
	Sep. 30, 2022	Oct. 20, 2022
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2022
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	Q3
Entity Registrant Name	ARMSTRONG WORLD INDUSTRIES, INC.
Trading Symbol	AWI
Entity Central Index Key	0000007431
Entity Current Reporting Status	Yes
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Common Stock, Shares Outstanding		45,662,803
Entity Shell Company	false
Entity File Number	1-2116
Entity Tax Identification Number	23-0366390
Entity Address, Address Line One	2500 Columbia Avenue
Entity Address, City or Town	Lancaster
Entity Address, State or Province	PA
Entity Address, Postal Zip Code	17603
City Area Code	717
Local Phone Number	397-0611
Entity Interactive Data Current	Yes
Document Quarterly Report	true
Document Transition Report	false
Entity Incorporation, State or Country Code	PA
Security Exchange Name	NYSE
Title of 12(b) Security	Common Stock, $0.01 par value per share