Basis of Presentation and Summary of Significant Accounting Policies - Investment Categories (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Amortized cost	$ 127,996	$ 292,225
Gross unrealized gains	436	842
Gross unrealized losses	(5,184)	(2,370)
Estimated fair value	123,248	290,697
Total short-term investments	142,655	321,586
Bank deposits
Debt Securities, Available-for-sale [Line Items]
Amortized cost	2,504	63,389
Gross unrealized gains	0	13
Gross unrealized losses	(61)	(21)
Estimated fair value	2,443	63,381
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Amortized cost	4,904	29,308
Gross unrealized gains	0	17
Gross unrealized losses	(121)	(38)
Estimated fair value	4,783	29,287
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized cost		36,008
Gross unrealized gains		2
Gross unrealized losses		(12)
Estimated fair value		35,998
Corporate equity securities
Debt Securities, Available-for-sale [Line Items]
Amortized cost	5,807	5,807
Gross unrealized gains	307	402
Gross unrealized losses	(3,703)	(2,027)
Estimated fair value	2,411	4,182
Mutual fund
Debt Securities, Available-for-sale [Line Items]
Amortized cost	112,535	152,136
Gross unrealized gains	0	0
Gross unrealized losses	(1,228)	(249)
Estimated fair value	111,307	151,887
US government securities
Debt Securities, Available-for-sale [Line Items]
Amortized cost	2,246	5,577
Gross unrealized gains	0	0
Gross unrealized losses	(71)	(23)
Estimated fair value	2,175	5,554
Warrants
Debt Securities, Available-for-sale [Line Items]
Amortized cost	0	0
Gross unrealized gains	129	408
Gross unrealized losses	0	0
Estimated fair value	129	408
Common Stock
Debt Securities, Available-for-sale [Line Items]
Viking common stock	$ 19,407	$ 30,889

Debt Securities, Available-For-Sale And Equity Securities, FV-NI

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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

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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), classified as current.

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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.

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