Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding.

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-Publisher FASB
-Name Accounting Standards Codification
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SCHEDULE II CONDENSED FINANCIAL INFORMATION OF REGISTRANT PARENT COMPANY ONLY (BALANCE SHEETS) (Parenthetical) (Details) - USD ($) $ in Millions		12 Months Ended
	Dec. 28, 2018	Dec. 31, 2018	Dec. 30, 2018
Condensed Financial Statements Captions [Line Items]
Net proceeds from sale of Chaucer business		$ 635.7
The Hanover Insurance Group [Member]
Condensed Financial Statements Captions [Line Items]
Net proceeds from sale of Chaucer business		762.0
Dividends declared			$ 193.4
The Hanover Insurance Group [Member] \| Chaucer [Member]
Condensed Financial Statements Captions [Line Items]
Net proceeds from sale of Chaucer business	$ 762.0
Receivable		$ 31.7