SCHEDULE IV REINSURANCE	12 Months Ended
Dec. 31, 2023
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Abstract]
SCHEDULE IV REINSURANCE	SCHEDULE IV THE HANOVER INSURANCE GROUP, INC. REINSURANCE Incorporated herein by reference to Note 13 — “Reinsurance” in the Notes to Consolidated Financial Statements.

The entire disclosure for the supplemental schedule of reinsurance information. Reinsurance schedule includes, but is not limited to, the type of insurance, gross amount of premiums, premiums ceded to other entities, premiums assumed from other entities, net amount of premium revenue, and the percentage of the premiums assumed to net premium revenue.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Subsection 17
-Publisher SEC

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 235
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.12-17)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480149/944-235-S99-2

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