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Retirement Plans - Additional Information (Detail) $ in Millions	6 Months Ended
	Jun. 30, 2019 USD ($)
United States Plans
Defined Benefit Plan Disclosure
Contribution to defined benefit pension plans	$ 1.3
U.S. Supplemental Executive Defined Benefit Pension Plan
Defined Benefit Plan Disclosure
Contribution to defined benefit pension plans	$ 0.4

X

- Definition

Amount of contribution received by defined benefit plan from employer which increases plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 55
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-Publisher FASB
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-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Details

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Namespace Prefix:
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Balance Type:
Period Type:

X

- Details

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Namespace Prefix:
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Balance Type:
Period Type: