Leases - Future Minimum Lease Payments Under Non-Cancellable Leases (Detail) - USD ($)	Sep. 30, 2020	Dec. 31, 2019
Operating Leases
Remainder of 2020	$ 221,000
2021	889,000
2022	849,000
2023	815,000
2024 and beyond	1,176,000
Total future minimum lease payments	3,950,000
Less imputed interest	(922,000)
Total	3,028,000	$ 3,379,000
Finance Leases
Remainder of 2020	14,000
2021	55,000
Total future minimum lease payments	69,000
Less imputed interest	(5,000)
Total	$ 64,000	$ 0

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Present value of lessee's discounted obligation for lease payments from finance lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918701-209980

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-Section 45
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918627-209977

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Amount of lessee's undiscounted obligation for lease payments for finance lease.

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+ References

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Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in remainder of current fiscal year.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918701-209980

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
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