Cover Page	12 Months Ended
	Dec. 31, 2021 USD ($) shares
Cover [Abstract]
Document Type	10-K/A
Entity Interactive Data Current	Yes
Amendment Flag	true
Amendment Description	With respect to the number of units for Class A Series 1 (for the Limited Partners only) and Class B Series 1, a system generated, administrative error resulted in the incorrect number of units being rolled forward in the Statement of Changes in Partners’ Capital. Hence, we have rectified the error by changing the number of units disclosed as part of the December 2019 closing balances and, thus the opening balances for the number of units carried forward to January 2020. Furthermore, we have carried out additional checks and can confirm that this issue was not pervasive across other areas of the Statement of Changes in Partners’ Capital, nor did it exist in the Statement of Financial Condition.
Document Period End Date	Dec. 31, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	FY
Trading Symbol	MADL
Entity Registrant Name	MAN AHL DIVERSIFIED I LP
Entity Central Index Key	0001052354
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Title of 12(b) Security	NONE
Security Exchange Name	NONE
Entity Shell Company	false
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding | shares	0
Entity Address, State or Province	NY
Document Transition Report	false
Entity File Number	000-53043
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	06-1496634
Entity Address, Address Line One	452 5th Avenue
Entity Address, Address Line Two	27th Floor
Entity Address, City or Town	New York
Entity Address, Postal Zip Code	10018
City Area Code	212
Local Phone Number	649-6600
Entity Public Float | $	$ 0
Entity Voluntary Filers	No
Entity Well-known Seasoned Issuer	No
ICFR Auditor Attestation Flag	false
Document Annual Report	true
Auditor Name	Ernst & Young Ltd.
Auditor Firm ID	1655
Auditor Location	Cayman Islands