Financial Instruments - Schedule of Assets, Liabilities, and Equity Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Assets
Short-term investments	$ 95,458	$ 33,737
Fair Value, Measurements, Recurring
Assets
Cash equivalents	398,651	509,971
Short-term investments	95,458	33,737
Loans held for sale	23,693	35,759
Other current assets	2,097	1,329
Long-term investments	56,194	54,828
Total assets	576,093	635,624
Liabilities
Total liabilities	307	153
Fair Value, Measurements, Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Cash equivalents	398,651	509,971
Loans held for sale	0	0
Other current assets	0	0
Total assets	550,303	598,536
Liabilities
Total liabilities	0	0
Fair Value, Measurements, Recurring \| Significant Other Observable Inputs (Level 2)
Assets
Cash equivalents	0	0
Loans held for sale	23,693	35,759
Other current assets	1,547	138
Total assets	25,240	35,897
Liabilities
Total liabilities	0	93
Fair Value, Measurements, Recurring \| Significant Unobservable Inputs (Level 3)
Assets
Cash equivalents	0	0
Loans held for sale	0	0
Other current assets	550	1,191
Total assets	550	1,191
Liabilities
Total liabilities	307	60
Fair Value, Measurements, Recurring \| Money market funds
Assets
Cash equivalents	398,651	509,971
Fair Value, Measurements, Recurring \| Money market funds \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Cash equivalents	398,651	509,971
Fair Value, Measurements, Recurring \| Money market funds \| Significant Other Observable Inputs (Level 2)
Assets
Cash equivalents	0	0
Fair Value, Measurements, Recurring \| Money market funds \| Significant Unobservable Inputs (Level 3)
Assets
Cash equivalents	0	0
U.S. treasury securities \| Fair Value, Measurements, Recurring
Assets
Short-term investments	88,555	16,718
Long-term investments	56,194	54,828
U.S. treasury securities \| Fair Value, Measurements, Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Short-term investments	88,555	16,718
Long-term investments	56,194
U.S. treasury securities \| Fair Value, Measurements, Recurring \| Significant Other Observable Inputs (Level 2)
Assets
Short-term investments	0	0
Long-term investments	0
U.S. treasury securities \| Fair Value, Measurements, Recurring \| Significant Unobservable Inputs (Level 3)
Assets
Short-term investments	0	0
Long-term investments	0
Agency bonds \| Fair Value, Measurements, Recurring
Assets
Short-term investments	6,903	11,906
Long-term investments	0	0
Agency bonds \| Fair Value, Measurements, Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Short-term investments	6,903	11,906
Long-term investments		54,828
Agency bonds \| Fair Value, Measurements, Recurring \| Significant Other Observable Inputs (Level 2)
Assets
Short-term investments	0	0
Long-term investments		0
Agency bonds \| Fair Value, Measurements, Recurring \| Significant Unobservable Inputs (Level 3)
Assets
Short-term investments	0	0
Long-term investments		0
Equity securities
Assets
Short-term investments		5,113
Equity securities \| Fair Value, Measurements, Recurring
Assets
Short-term investments		5,113
Long-term investments		0
Equity securities \| Fair Value, Measurements, Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Short-term investments		5,113
Equity securities \| Fair Value, Measurements, Recurring \| Significant Other Observable Inputs (Level 2)
Assets
Short-term investments		0
Equity securities \| Fair Value, Measurements, Recurring \| Significant Unobservable Inputs (Level 3)
Assets
Short-term investments		0
Forward sales commitments \| Fair Value, Measurements, Recurring
Assets
Other current assets	1,547	138
Liabilities
Accrued liabilities	0	93
Forward sales commitments \| Fair Value, Measurements, Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Other current assets	0	0
Liabilities
Accrued liabilities	0	0
Forward sales commitments \| Fair Value, Measurements, Recurring \| Significant Other Observable Inputs (Level 2)
Assets
Other current assets	1,547	138
Liabilities
Accrued liabilities	0	93
Forward sales commitments \| Fair Value, Measurements, Recurring \| Significant Unobservable Inputs (Level 3)
Assets
Other current assets	0	0
Liabilities
Accrued liabilities	0	0
IRLCs \| Fair Value, Measurements, Recurring
Assets
Other current assets	550	1,191
Liabilities
Accrued liabilities	307	60
IRLCs \| Fair Value, Measurements, Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Other current assets	0	0
Liabilities
Accrued liabilities	0	0
IRLCs \| Fair Value, Measurements, Recurring \| Significant Other Observable Inputs (Level 2)
Assets
Other current assets	0	0
Liabilities
Accrued liabilities	0	0
IRLCs \| Fair Value, Measurements, Recurring \| Significant Unobservable Inputs (Level 3)
Assets
Other current assets	550	1,191
Liabilities
Accrued liabilities	$ 307	$ 60

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

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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), classified as current.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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