Investments - Schedule of Available-for-sale Securities in Continuous Unrealized Loss Position (Details) $ in Thousands	Mar. 31, 2022 USD ($) security	Dec. 31, 2021 USD ($) security
Debt Securities, Available-for-sale [Line Items]
Less than or equal to one year, fair value	$ 440,104	$ 344,073
Less than or equal to one year, gross unrealized losses	$ (22,873)	$ (4,403)
Less than or equal to one year, number of securities \| security	1,121	762
More than one year, fair value	$ 60,816	$ 25,110
More than one year, gross unrealized loss	$ (7,093)	$ (2,707)
More than one year, number of securities \| security	220	102
U.S. Treasury securities and obligations of U.S. government authorities and agencies
Debt Securities, Available-for-sale [Line Items]
Less than or equal to one year, fair value	$ 276,483	$ 216,378
Less than or equal to one year, gross unrealized losses	$ (13,589)	$ (2,827)
Less than or equal to one year, number of securities \| security	524	324
More than one year, fair value	$ 35,661	$ 11,920
More than one year, gross unrealized loss	$ (3,068)	$ (370)
More than one year, number of securities \| security	119	47
Obligations of state and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Less than or equal to one year, fair value	$ 26,377	$ 17,190
Less than or equal to one year, gross unrealized losses	$ (2,227)	$ (275)
Less than or equal to one year, number of securities \| security	93	64
More than one year, fair value	$ 2,828	$ 1,152
More than one year, gross unrealized loss	$ (232)	$ (38)
More than one year, number of securities \| security	18	5
Corporate securities
Debt Securities, Available-for-sale [Line Items]
Less than or equal to one year, fair value	$ 123,495	$ 99,434
Less than or equal to one year, gross unrealized losses	$ (6,572)	$ (1,159)
Less than or equal to one year, number of securities \| security	430	326
More than one year, fair value	$ 17,396	$ 9,722
More than one year, gross unrealized loss	$ (1,400)	$ (237)
More than one year, number of securities \| security	72	45
Asset backed securities
Debt Securities, Available-for-sale [Line Items]
Less than or equal to one year, fair value	$ 11,066	$ 7,454
Less than or equal to one year, gross unrealized losses	$ (414)	$ (84)
Less than or equal to one year, number of securities \| security	67	38
More than one year, fair value	$ 3,800	$ 2,316
More than one year, gross unrealized loss	$ (2,297)	$ (2,062)
More than one year, number of securities \| security	7	5
Certificates of deposit
Debt Securities, Available-for-sale [Line Items]
Less than or equal to one year, fair value	$ 1,339	$ 1,339
Less than or equal to one year, gross unrealized losses	$ 0	$ 0
Less than or equal to one year, number of securities \| security	2	2
More than one year, fair value	$ 0	$ 0
More than one year, gross unrealized loss	$ 0	$ 0
More than one year, number of securities \| security	0	0
Obligations of foreign governments
Debt Securities, Available-for-sale [Line Items]
Less than or equal to one year, fair value	$ 1,344	$ 2,278
Less than or equal to one year, gross unrealized losses	$ (71)	$ (58)
Less than or equal to one year, number of securities	5	8
More than one year, fair value	$ 1,131	$ 0
More than one year, gross unrealized loss	$ (96)	$ 0
More than one year, number of securities	4	0

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 50
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without an allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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