Cover Page - USD ($) $ in Billions	12 Months Ended
	Dec. 31, 2019	Feb. 14, 2020	Jun. 28, 2019
Cover page.
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2019
Document Transition Report	false
Entity File Number	001-32641
Entity Registrant Name	BROOKDALE SENIOR LIVING INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	20-3068069
Entity Address, Address Line One	111 Westwood Place,
Entity Address, Address Line Two	Suite 400,
Entity Address, City or Town	Brentwood,
Entity Address, State or Province	TN
Entity Address, Postal Zip Code	37027
City Area Code	(615)
Local Phone Number	221-2250
Title of 12(b) Security	Common Stock, $0.01 Par Value Per Share
Trading Symbol	BKD
Security Exchange Name	NYSE
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Public Float			$ 1.4
Entity Common Stock, Shares Outstanding		184,260,609
Entity Central Index Key	0001332349
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
Amendment Flag	false