Investments and Fair Value Measurements - Schedule of Financial Assets and Liabilities Subject to Fair Value Measurements (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Assets:
PropTech convertible trading debt securities	$ 3,598	$ 2,222
Long-term investments
Long-term investment securities at fair value	2,702	1,534
Total long-term investments	3,812	3,756
Quoted Prices in Active Markets for Identical Assets (Level 1) | Money market funds
Long-term investments
Current restricted assets	6,955	15,336
Non-current restricted assets	1,962	1,907
Recurring
Long-term investments
PropTech convertible trading debt securities	1,110	2,222
Long-term investment securities at fair value	2,702	1,534
Total long-term investments	3,812	3,756
Total assets	47,151	55,817
Recurring | Money market funds
Assets:
Cash and cash equivalents	40,282	51,492
Recurring | Certificates of deposit
Assets:
Cash and cash equivalents	569	569
PropTech convertible trading debt securities	2,488
Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Long-term investments
PropTech convertible trading debt securities	0	0
Long-term investment securities at fair value	0	0
Total long-term investments	0	0
Total assets	40,282	51,492
Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Money market funds
Assets:
Cash and cash equivalents	40,282	51,492
Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Certificates of deposit
Assets:
Cash and cash equivalents	0	0
PropTech convertible trading debt securities	0
Recurring | Significant Other Observable Inputs (Level 2)
Long-term investments
PropTech convertible trading debt securities	0	0
Long-term investment securities at fair value	0	0
Total long-term investments	0	0
Total assets	569	569
Recurring | Significant Other Observable Inputs (Level 2) | Money market funds
Assets:
Cash and cash equivalents	0	0
Recurring | Significant Other Observable Inputs (Level 2) | Certificates of deposit
Assets:
Cash and cash equivalents	569	569
PropTech convertible trading debt securities	0
Recurring | Significant Unobservable Inputs (Level 3)
Long-term investments
PropTech convertible trading debt securities	1,110	2,222
Long-term investment securities at fair value	0	0
Total long-term investments	1,110	2,222
Total assets	3,598	2,222
Recurring | Significant Unobservable Inputs (Level 3) | Money market funds
Assets:
Cash and cash equivalents	0	0
Recurring | Significant Unobservable Inputs (Level 3) | Certificates of deposit
Assets:
Cash and cash equivalents	0	$ 0
PropTech convertible trading debt securities	$ 2,488