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Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Millions |  | 3 Months Ended | 6 Months Ended
--- | --- | --- | ---
Jan. 01, 2020 | Mar. 31, 2020 | Jun. 30, 2019 | Jun. 30, 2019
Summary Of Significant Accounting Policy [Line Items] |  |  |  |
Life insurance proceeds received |  |  |  | $ 1.0
ASU 2018-15 [Member] | Reclassification of Property, Plant and Equipment to Other Assets [Member] |  |  |  |
Summary Of Significant Accounting Policy [Line Items] |  |  |  |
Effect on adoption of ASU | $ 5.6 |  |  |
Errors in Operating Activity [Member] |  |  |  |
Summary Of Significant Accounting Policy [Line Items] |  |  |  |
Amount of revision |  |  | $ 1.0 |
Overstatement Long-term Investment Balance at Remeasured Cost Basis [Member] |  |  |  |
Summary Of Significant Accounting Policy [Line Items] |  |  |  |
Amount of revision |  | $ 2.8 |  |
Errors in Net Investment Gain [Member] |  |  |  |
Summary Of Significant Accounting Policy [Line Items] |  |  |  |
Amount of revision |  | $ 1.5 |  |

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- Definition Amount of cash inflow for proceeds from settlement of corporate-owned life insurance policy, classified as investing activities. Includes, but is not limited to, bank-owned life insurance policy. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 21C -URI http://asc.fasb.org/extlink&oid=118932676&loc=SL94080552-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3179-108585 + Details
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