Debt instrument commencement of principal date.

No definition available.

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- Definition

Debt instrument repurchased face amount retired.

+ References

No definition available.

+ Details

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

- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

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+ Details

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

- Definition

Face (par) amount of debt instrument at time of issuance.

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+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Description of the frequency of periodic payments (monthly, quarterly, annual).

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Period Type:	duration

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- 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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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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+ Details

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Period Type:	duration

- Definition

Description of the payment terms of the debt instrument (for example, whether periodic payments include principal and frequency of payments) and discussion about any contingencies associated with the payment.

+ References

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Period Type:	duration

- Definition

Amount of the required periodic payments including both interest and principal payments.

+ References

+ Details

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

- Definition

Fair value amount of debt instrument that was repurchased.

+ References

No definition available.

+ Details

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

- Definition

Face (par) amount of the original debt instrument that was repurchased.

+ References

No definition available.

+ Details

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

- Definition

Amount of unamortized debt discount (premium) and debt issuance costs.

+ References

+ Details

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Balance Type:	debit
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- Definition

Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Balance Type:	debit
Period Type:	instant

- Definition

Amount of cash paid for interest, including, but not limited to, capitalized interest and payment to settle zero-coupon bond attributable to accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount; classified as operating and investing activities.

+ References

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+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- 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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Long-Term Debt - Additional Information (Detail) - USD ($)	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Oct. 31, 2018	Aug. 07, 2018	Apr. 30, 2018	Dec. 31, 2017	Nov. 30, 2017	Oct. 31, 2017	Aug. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Long-term debt	$ 196,986,000					$ 207,782,000
Net of issuance costs	$ 178,330,000					$ 184,405,000
Subsequent Event [Member] \| Convertible Note [Member]
Debt Instrument [Line Items]
Repurchase of convertible notes			$ 2,100,000
Repurchase of convertible notes, cost			2,500,000
Heritage P&C [Member] \| Convertible Note [Member]
Debt Instrument [Line Items]
Repurchase of convertible notes							$ 21,100,000
Repurchase of convertible notes, cost							$ 25,200,000
'Heritage Insurance Holdings, Inc. [Member] \| Convertible Note [Member]
Debt Instrument [Line Items]
Repurchase of convertible notes					$ 10,600,000
Repurchase of convertible notes, cost					$ 13,400,000
Senior Secured Notes [Member]
Debt Instrument [Line Items]
Long-term debt										$ 79,500,000
Interest rate	8.75%
Frequency of periodic interest payments	quarterly
Principal payment commencement date	Dec. 15, 2018
Net of issuance costs	$ 74,000,000
Issuance costs	5,300,000
Interest paid	6,600,000	$ 7,000,000
Convertible Senior Notes [Member]
Debt Instrument [Line Items]
Interest rate		5.875%							5.875%
Net of issuance costs	90,500,000
Interest paid	$ 7,700,000	$ 0
Aggregate principal amount		$ 136,800,000							$ 136,800,000
Notes maturity date	Aug. 01, 2037
Interest payments term	Interest accrues from August 16, 2017 and is payable semi-annually in arrears, on February 1 and August 1 of each year, beginning in 2018.
Net of issuance and debt discount costs	$ 11,000,000
Repurchase of convertible notes, retired				$ 10,600,000
Convertible Senior Notes [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Repurchase of convertible notes			3,100,000
Repurchase of convertible notes, cost			$ 3,600,000
Collateral Financial Arrangement [Member] \| Skye Lane Properties LLC [Member]
Debt Instrument [Line Items]
Interest rate								4.95%
Frequency of periodic interest payments	monthly
Aggregate principal amount								$ 12,700,000
Payment of principal and interest	$ 670,000