v3.19.2

Recent Accounting Pronouncements - Additional Information (Detail) - USD ($) | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2019 | Jun. 30, 2019 | Jan. 01, 2019
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |
Initial right-of-use assets | $ 4,179,000 | $ 4,179,000 |
Operating lease, expense | $ 305,000 | $ 653,000 |
ASU 2016 02 [Member] |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |
Initial right-of-use assets |  |  | $ 4,642,000

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- Definition Amount of operating lease expense. Excludes sublease income. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 4 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918638-209977 + Details
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- Definition Amount of lessee's right to use underlying asset under 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 (a) -URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977 + Details
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