The amount of increase in the benefit obligation attributed to business combinations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)(8)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

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- 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.

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- Definition

The amount of increase related to special termination benefits offered to and accepted by employees in connection with their termination of employment that are only offered for a short period of time. A situation involving termination benefits may also involve a curtailment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Termination Benefits
-URI http://asc.fasb.org/extlink&oid=6526498

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)(10)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

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Reconciliation of Benefit Obligations, Plan Assets, and Unfunded or Funded Status (Parenthetical) (Detail) - USD ($) $ in Millions		12 Months Ended
	Nov. 06, 2015	Dec. 31, 2016
Qualified defined benefit pension plans
Defined Benefit Plan Disclosure [Line Items]
Acquisition increased qualified defined benefit pension obligation	$ 30
Qualified defined benefit pension plans \| Information Systems & Global Solutions
Defined Benefit Plan Disclosure [Line Items]
Special termination benefits		$ 27
Retiree medical and life insurance plans \| Information Systems & Global Solutions
Defined Benefit Plan Disclosure [Line Items]
Special termination benefits		$ 9