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Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Thousands | Jan. 01, 2019 | Mar. 31, 2019
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Summary Of Significant Accounting Policy [Line Items] |  |
Operating lease, right-of-use asset | $ 10,322 | $ 9,502
Operating lease, right-of-use liability | 10,322 | $ 9,519
ASU 2018-02 [Member] |  |
Summary Of Significant Accounting Policy [Line Items] |  |
Reclassification of tax effects related to adoption ASU | $ 400 |

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- Definition 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) -URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977 + 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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