Reinsurance, Per Risk Limit, Amount

No definition available.

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Balance Type:	credit
Period Type:	duration

- Definition

Reinsurance Program, Minimum Losses Threshold

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Ratio of insurance contracts that are subject to reinsurance participation to all contracts in force.

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Amount per event of risk undertaken originally by insurer that is not ceded to reinsurer.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479838/944-20-50-3

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount per event of risk ceded to reinsurer in excess of risk undertaken originally by insurer that is not ceded to reinsurer.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount per policy of risk ceded to reinsurer in excess of risk undertaken originally by insurer that is not ceded to reinsurer.

+ References

+ Details

Name:	us-gaap_ReinsuranceRetentionExcessRetentionAmountReinsuredPerPolicy
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Percentage of risk ceded to reinsurer in excess of risk undertaken originally by insurer that is not ceded to reinsurer.

+ References

+ Details

Name:	us-gaap_ReinsuranceRetentionPolicyExcessRetentionPercentage
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of risk undertaken originally by insurer ceded to reinsurer.

+ References

+ Details

Name:	us-gaap_ReinsuranceRetentionPolicyReinsuredRiskPercentage
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, after effects of reinsurance, of expense for claims incurred in the current reporting period and related claims settlement costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480081/944-40-50-3

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount, after effects of reinsurance, of expense (reversal of expense) for claims incurred in prior reporting periods and related claims settlement costs.

+ References

+ Details

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Balance Type:	debit
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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Unpaid Loss and Loss Adjustment Expense - Additional Information (Details) - USD ($)			6 Months Ended	9 Months Ended		12 Months Ended
	Jul. 01, 2023	Jul. 01, 2022	Jun. 30, 2021	Sep. 30, 2023	Sep. 30, 2022	Jun. 30, 2022
Effects of Reinsurance [Line Items]
Favorable development on net loss and LAE reserves				$ (3,600,000)	$ (1,100,000)
Current accident year incurred loss and LAE				$ 219,000,000.0	$ 106,900,000
Reinsurance program, minimum losses threshold		$ 80,000,000
Reinsurance, per risk limit, amount	$ 750,000
Reinsurance, excess retention, amount reinsured, per event	5,000,000
Reinsurance Contract [Axis]: Automatic Facultative Property Per Risk Excess of Loss \| Lemonade Insurance Company
Effects of Reinsurance [Line Items]
Reinsurance, excess retention, amount reinsured, per policy	3,000,000
Reinsurance Contract [Axis]: Automatic Facultative Property Per Risk Excess of Loss Reinsurance \| Lemonade Insurance Company
Effects of Reinsurance [Line Items]
Reinsurance, excess retention, amount reinsured, per policy	$ 10,000,000
Reinsurance, excess retention, percentage	100.00%
Reinsurance Contract [Axis]: Excess of Loss Reinsurance Contract
Effects of Reinsurance [Line Items]
Initial limit for each loss occurrence	$ 50,000,000
Reinsurance, excess retention, amount reinsured, per event	80,000,000
Reinsurance Contract [Axis]: Premiums and Losses to Reinsurers
Effects of Reinsurance [Line Items]
Reinsurance, reinsured risk, percentage				30.00%
Reinsurance Contract [Axis]: Property Per Risk Excess of Loss Reinsurance
Effects of Reinsurance [Line Items]
Reinsurance, excess retention, amount reinsured, per policy	$ 2,250,000
Reinsurance, excess retention, percentage	100.00%
Reinsurance Contract [Axis]: Property Per Risk Excess of Loss Reinsurance \| Maximum
Effects of Reinsurance [Line Items]
Reinsurance, excess retention, amount reinsured, per policy	$ 750,000
Reinsurance Contract [Axis]: Proportional Reinsurance Contracts
Effects of Reinsurance [Line Items]
Percent of contracts subject to participation through reinsurance	55.00%	55.00%	75.00%			70.00%
Winter Storm Elliot
Effects of Reinsurance [Line Items]
Current accident year incurred loss and LAE				$ 10,000,000
Texas Hail Storm
Effects of Reinsurance [Line Items]
Current accident year incurred loss and LAE				$ 3,500,000