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Equity Investments Acquired as Part of Business Combination (Parenthetical) (Detail)	Dec. 31, 2016
Getrag (Jiangxi) Transmission Co., Ltd [GJT] [Member]
Schedule of Equity Method Investments [Line Items]
Percentage of ownership interest	66.70%
Consolidated subsidiary [Member]
Schedule of Equity Method Investments [Line Items]
Percentage of non-controlling interest	25.00%

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- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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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.

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