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Accounting Standards Adopted in Current Year - Additional Information (Detail) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
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Mar. 31, 2018 | Jun. 30, 2018 | [1]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |
Tax Act from accumulated other comprehensive loss to retained earnings | $ 2,485 | $ 2,485
Intra-Entity Transfers of Assets Other Than Inventory |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |
Cumulative adjustment to decrease retained earnings | $ 48,624 |
[1] | Amounts in parentheses indicate debits

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- Definition Amount of the cumulative effect on retained earnings net of related income tax effect. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22663-107794 + Details
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- Definition Tax Cuts and Jobs Act of 2017, reclassification from AOCI to retained earnings, tax effect. + References No definition available. + Details
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