Fair Value Measurements (Details) - USD ($)	6 Months Ended	12 Months Ended
	Jul. 31, 2021	Jan. 31, 2021
Short-term investments:
Short-term investments	$ 370,000	$ 364,000
Total assets measured and recorded at fair value	40,890,000	40,882,000
Debt securities, available-for-sale, unrealized gain (loss)	0	0
Level 1
Short-term investments:
Total assets measured and recorded at fair value	40,520,000	40,518,000
Level 2
Short-term investments:
Total assets measured and recorded at fair value	370,000	364,000
Level 3
Short-term investments:
Total assets measured and recorded at fair value	0	0
Certificates of deposit
Short-term investments:
Short-term investments	370,000	364,000
Certificates of deposit | Level 1
Short-term investments:
Short-term investments	0	0
Certificates of deposit | Level 2
Short-term investments:
Short-term investments	370,000	364,000
Certificates of deposit | Level 3
Short-term investments:
Short-term investments	0	0
Money market funds
Cash equivalents:
Money market funds	40,520,000	40,518,000
Money market funds | Level 1
Cash equivalents:
Money market funds	40,520,000	40,518,000
Money market funds | Level 2
Cash equivalents:
Money market funds	0	0
Money market funds | Level 3
Cash equivalents:
Money market funds	$ 0	$ 0