Schedule of Minimum Rental Payments To Be Received (Detail) $ in Thousands	Dec. 31, 2019 USD ($)
Property, Plant and Equipment [Line Items]
Total	$ 1,836
Buildings \| Wuxi Zastron Precision-Flex Co., Ltd. (Wuxi Zastron-Flex)
Property, Plant and Equipment [Line Items]
2020	957
2021	973
2022	1,053
2023	1,053
2024 and thereafter	8,121
Total	$ 12,157

Future minimum rental payments in aggregate as of the balance sheet date under operating leases.

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84164653&loc=d3e41551-112718

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Future rental payments receivable within the fourth year from the balance sheet date under an operating lease.

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