Other Long-Term Liabilities - Schedule of Other Non Current Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Other Liabilities, Noncurrent [Abstract]
Customer deposits	$ 750	$ 850
Restructuring liability	49	342
Other long-term liabilities	4	44
Total other long-term liabilities	$ 803	$ 1,236

Noncurrent regulatory liabilities generally represent obligations to make refunds to customers for various reasons including overpayment.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.24)
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

+ 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)
-URI https://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977

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- Definition

Amount of liabilities classified as other, due after one year or the normal operating cycle, if longer.

+ References

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- References

No definition available.

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- Definition

Carrying amount as of the balance sheet date of known and estimated costs associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid after one year or beyond the next operating cycle, if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, and relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph 210-10-S99-1(SX 210.5-02(24))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI https://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 5.P.4(b)(2))
-URI https://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747

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