Document and Entity Information - USD ($)	9 Months Ended
	Sep. 30, 2015	Oct. 23, 2015
Document And Entity Information [Abstract]
Entity Registrant Name	WELLTOWER INC. /DE/
Entity Central Index Key	0000766704
Document Type	10-Q
Document Period End date	Sep. 30, 2015
Amendment Flag	false
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q3
Current Fiscal Year End Date	--12-31
Entity Well Known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Public Float	$ 23,029,716,957
Entity Common Stock Shares Outstanding		353,879,510