Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Significant Accounting Policies [Line Items]
Changes in assumptions and experience gains and losses	greater than 10%
Period of benefit obligation in current liabilities	next twelve months
Sales	$ 39,431.0	$ 40,827.0
Unbilled accounts receivable	318.0	293.0
Deferred revenue	199.0	176.0
Deferred revenue recognized	91.0	0.0
Research and development costs	640.0	588.0
Tooling And Engineering [Member]
Significant Accounting Policies [Line Items]
Sales	749.1	824.6
Accounts receivable	$ 4,500.0	$ 4,300.0
Minimum [Member]
Significant Accounting Policies [Line Items]
Estimated useful lives of finite-lived intangible assets	4 years
Contract with customer agreement termination period	5 years
Payment term Duration	30 days
Minimum [Member] \| Building [Member]
Significant Accounting Policies [Line Items]
Annual rates of depreciation on fixed assets	2.50%
Minimum [Member] \| General Purpose Equipment [Member]
Significant Accounting Policies [Line Items]
Annual rates of depreciation on fixed assets	7.00%
Minimum [Member] \| Special Purpose Equipment [Member]
Significant Accounting Policies [Line Items]
Annual rates of depreciation on fixed assets	10.00%
Maximum [Member]
Significant Accounting Policies [Line Items]
Estimated useful lives of finite-lived intangible assets	15 years
Contract with customer agreement termination period	7 years
Payment term Duration	90 days
Maximum [Member] \| Building [Member]
Significant Accounting Policies [Line Items]
Annual rates of depreciation on fixed assets	5.00%
Maximum [Member] \| General Purpose Equipment [Member]
Significant Accounting Policies [Line Items]
Annual rates of depreciation on fixed assets	10.00%
Maximum [Member] \| Special Purpose Equipment [Member]
Significant Accounting Policies [Line Items]
Annual rates of depreciation on fixed assets	33.00%

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- Definition

Assumptions of employee future benefit plans description.

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Period of benefit obligation in current liabilities.

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Property plant and equipment depreciation rate.

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Significant Accounting Policies [Line Items]

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- Definition

Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

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Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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Unbilled amounts due for services rendered or to be rendered, actions taken or to be taken, or a promise to refrain from taking certain actions in accordance with the terms of a legally binding agreement between the entity and, at a minimum, one other party. An example would be amounts associated with contracts or programs where the recognized revenue for performance thereunder exceeds the amounts billed under the terms thereof as of the date of the balance sheet.

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