Fair Value Measurements - Financial Assets and Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Assets:
Fair Value	$ 478,477	$ 432,682
Equity securities at fair value	37,509	33,261
U.S. Governments
Assets:
Fair Value	45,168	16,870
States, territories, and possessions
Assets:
Fair Value	5,580	4,014
Political subdivisions
Assets:
Fair Value	6,043	6,380
Special revenue excluding mortgage/asset-backed securities
Assets:
Fair Value	38,977	44,498
Corporate and other
Assets:
Fair Value	246,407	249,046
Mortgage/asset-backed securities
Assets:
Fair Value	136,301	111,874
Fair Value, Measurements, Recurring
Assets:
Equity securities at fair value	37,509	33,261
Cash, cash equivalents, and restricted cash	36,508	50,371
Total assets	552,493	516,314
Fair Value, Measurements, Recurring \| U.S. Governments
Assets:
Fair Value	45,168	16,870
Fair Value, Measurements, Recurring \| States, territories, and possessions
Assets:
Fair Value	5,580	4,014
Fair Value, Measurements, Recurring \| Political subdivisions
Assets:
Fair Value	6,043	6,380
Fair Value, Measurements, Recurring \| Special revenue excluding mortgage/asset-backed securities
Assets:
Fair Value	38,977	44,498
Fair Value, Measurements, Recurring \| Corporate and other
Assets:
Fair Value	246,407	249,046
Fair Value, Measurements, Recurring \| Mortgage/asset-backed securities
Assets:
Fair Value	136,301	111,874
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 1
Assets:
Equity securities at fair value	37,509	33,261
Cash, cash equivalents, and restricted cash	36,508	50,371
Total assets	74,017	83,632
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 2
Assets:
Total assets	478,476	431,182
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 2 \| U.S. Governments
Assets:
Fair Value	45,168	16,870
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 2 \| States, territories, and possessions
Assets:
Fair Value	5,580	4,014
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 2 \| Political subdivisions
Assets:
Fair Value	6,043	6,380
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 2 \| Special revenue excluding mortgage/asset-backed securities
Assets:
Fair Value	38,977	44,498
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 2 \| Corporate and other
Assets:
Fair Value	246,407	249,046
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 2 \| Mortgage/asset-backed securities
Assets:
Fair Value	$ 136,301	110,374
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 3
Assets:
Total assets		1,500
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 3 \| Mortgage/asset-backed securities
Assets:
Fair Value		$ 1,500

Fair value portion of cash, cash equivalents and restricted cash.

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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