Investment Agreement, Performance Agreement, Purchase Obligation Amount

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- Definition

Preferred Stock, Redemption Features, Period to Call

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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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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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- Definition

Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.

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- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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- Definition

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

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No definition available.

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Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions.

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- Definition

The cash outflow associated with the acquisition of or advances to an entity that is related to it but not strictly controlled (for example, an unconsolidated subsidiary, affiliate, and joint venture or equity method investment) or the acquisition of an additional interest in a subsidiary (controlled entity).

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The percentage rate used to calculate dividend payments on preferred stock.

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No definition available.

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The per share liquidation preference (or restrictions) of nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) that has a preference in involuntary liquidation considerably in excess of the par or stated value of the shares. The liquidation preference is the difference between the preference in liquidation and the par or stated values of the share.

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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

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Aggregate par or stated value of issued nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable preferred shares, par value and other disclosure concepts are in another section within stockholders' equity.

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The cash inflow from issuance of preferred stocks identified as being convertible into another form of financial instrument, typically the entity's common stock.

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- Definition

Minimum amount of purchase arrangement in which the entity has agreed to expend funds to procure goods or services from a supplier.

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No definition available.

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Stockholders' Equity and Noncontrolling Interests Preferred and Common Stock (Details) - USD ($)	1 Months Ended			3 Months Ended		9 Months Ended
	Sep. 30, 2018	Jun. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2027	May 31, 2018	Dec. 31, 2017
Stockholders' Equity Note [Abstract]
Preferred stock shares authorized (in shares)	2,000,000,000.0			2,000,000,000.0		2,000,000,000.0				2,000,000,000.0
Common stock shares authorized (in shares)	5,000,000,000.0			5,000,000,000.0		5,000,000,000.0				5,000,000,000.0
Common stock shares issued (in shares)	1,400,000,000			1,400,000,000		1,400,000,000				1,400,000,000
Common stock shares outstanding (in shares)	1,400,000,000			1,400,000,000		1,400,000,000				1,400,000,000
Common shares purchased during period (in shares)						3,000,000	86,000,000
Common shares purchased during period						$ 100,000,000	$ 2,994,000,000
Total dividends paid on common stock				$ 537,000,000	$ 546,000,000	1,608,000,000	1,683,000,000
Class of Stock [Line Items]
Maximum financial guarantees	$ 6,000,000,000			6,000,000,000		6,000,000,000				$ 5,100,000,000
GM Cruise Holdings LLC [Member]
Class of Stock [Line Items]
Investment amount		$ 1,100,000,000
GM Korea [Member] \| Forecast [Member]
Class of Stock [Line Items]
Planned capital expenditures								$ 2,000,000,000
GM Korea [Member] \| Financial Guarantee [Member]
Class of Stock [Line Items]
Maximum financial guarantees	2,800,000,000.0			2,800,000,000.0		$ 2,800,000,000.0
Convertible Preferred Shares [Member] \| GM Cruise Holdings LLC [Member]
Class of Stock [Line Items]
Proceeds from issuance of preferred stock		$ 900,000,000
Annual dividend rate						7.00%
SoftBank Investment Holdings [Member] \| Convertible Preferred Shares [Member] \| GM Cruise Holdings LLC [Member]
Class of Stock [Line Items]
Ownership interest		10.90%
Additional purchase amount	1,350,000,000			1,350,000,000		$ 1,350,000,000
Korea Development Bank [Member] \| Class B Preferred Shares [Member] \| GM Korea [Member]
Class of Stock [Line Items]
Proceeds from issuance of preferred stock		$ 361,000,000
Annual dividend rate						1.00%
Period to call preferred shares		6 years
Preferred stock purchase arrangement									$ 750,000,000
GM Financial [Member] \| Fixed-to-Floating Rate Cumulative Perpetual Preferred Stock, Series B [Member]
Class of Stock [Line Items]
Preferred stock issued	$ 500,000,000			$ 500,000,000		$ 500,000,000
Preferred stock par value (in dollars per share)	$ 0.01			$ 0.01		$ 0.01
Preferred stock liquidation preference (in dollars per share)	$ 1,000			$ 1,000		$ 1,000
Annual dividend rate	6.50%
GM Financial [Member] \| Fixed-to-Floating Rate Cumulative Perpetual Preferred Stock, Series A [Member]
Class of Stock [Line Items]
Preferred stock issued			$ 1,000,000,000		$ 1,000,000,000		$ 1,000,000,000
Preferred stock par value (in dollars per share)			$ 0.01		$ 0.01		$ 0.01
Preferred stock liquidation preference (in dollars per share)			$ 1,000		$ 1,000		$ 1,000
Annual dividend rate			5.75%