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.

No definition available.

+ Details

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- Definition

Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 55
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=112275985&loc=d3e4179-114921

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920

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- Definition

Percentage of actual investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920

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Schedule of Pension Plans Weighted-Average Asset Allocation and Range of Target Allocation (Detail)	Mar. 31, 2019	Mar. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Percentage of Plan Assets at March 31	100.00%	100.00%
Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of Plan Assets at March 31	14.00%	50.00%
Equity Securities [Member] \| Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Range of Target Allocation	10.00%
Equity Securities [Member] \| Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Range of Target Allocation	20.00%
Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of Plan Assets at March 31	85.00%	47.00%
Debt Securities [Member] \| Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Range of Target Allocation	60.00%
Debt Securities [Member] \| Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Range of Target Allocation	90.00%
Other [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of Plan Assets at March 31	1.00%	3.00%
Other [Member] \| Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Range of Target Allocation	0.00%
Other [Member] \| Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Range of Target Allocation	20.00%