Bank holding companies with assets greater than $50 billion must develop and maintain a capital plan annually.

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- Definition

Percentage Of Tier One Common Risk Based Capital to Risk Weighted Assets

+ References

No definition available.

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- Definition

Capital plan must include discussion of how bank holding companies will keep Tier 1 common ratio above 5 percent under certain conditions.

+ References

No definition available.

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- Definition

The minimum amount of Tier 1 Leverage Capital for capital adequacy purposes divided by average assets in accordance with CLMA requirements for Ally Bank.

+ References

No definition available.

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- Definition

Tier One Common Risk Based Capital

+ References

No definition available.

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- Definition

The amount of total capital as defined in the regulations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 948

-SubTopic 10

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6490092&loc=d3e47304-110998

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 505

-Section 50

-Paragraph 1H

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-Name Accounting Standards Codification

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-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

-Section 50

-Paragraph 3

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- Definition

The minimum Total risk based capital ratio (total capital divided by risk weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 505

-Section 50

-Paragraph 1H

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=7881181&loc=d3e65071-112826

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-Publisher FASB

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-Topic 942

-SubTopic 505

-Section 50

-Paragraph 1

-Subparagraph (c)(1)

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-Section 50

-Paragraph 1B

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- Definition

The Total risk based capital ratio (total capital divided by risk weighted assets) required to be categorized as "well capitalized", in the regulatory framework for prompt corrective action.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 505

-Section 50

-Paragraph 1

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=7881181&loc=SL5958568-112826

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- Definition

Total Capital divided by risk weighted assets as defined in the regulations.

+ References

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- Definition

Tier 1 Leverage Capital as defined in the regulations. Also called Core Capital.

+ References

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- Definition

The minimum amount of Tier 1 Leverage Capital for capital adequacy purposes divided by average assets as defined in the regulations.

+ References

+ Details

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- Definition

The amount of Tier 1 Leverage Capital required to be categorized as well capitalized divided by average assets as defined in the regulatory framework for prompt corrective action.

+ References

+ Details

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- Definition

Tier 1 Leverage Capital divided by average assets as defined in the regulations.

+ References

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- Definition

Tier 1 Risk Based Capital as defined in the regulations.

+ References

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- Definition

The minimum Tier One Capital Ratio (Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

+ References

+ Details

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- Definition

The Tier 1 capital ratio (Tier 1 capital divided by risk weighted assets) required to be categorized as "well capitalized" under the regulatory framework for prompt corrective action.

+ References

+ Details

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- Definition

Tier 1 capital divided by risk weighted assets as defined by regulations.

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Regulatory Capital (Schedule Of Regulatory Capital Amount And Ratios) (Details) (USD $)	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2013 Parent Company [Member]	Dec. 31, 2012 Parent Company [Member]	Sep. 30, 2013 Parent Company [Member] Minimum [Member]	Sep. 30, 2013 Parent Company [Member] Maximum [Member]	Sep. 30, 2013 Ally Bank [Member]	Dec. 31, 2012 Ally Bank [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
assets greater than $50 billion	$ 50,000,000,000
Tier 1 common ratio above 5 percent	5.00%
Tier 1 (to risk-weighted assets), Amount		19,571,000,000	20,232,000,000			14,926,000,000	14,136,000,000
Tier 1 (to risk-weighted assets), Ratio		15.37%	13.13%			17.90%	16.26%
Tier 1 (to risk-weighted assets), Required minimum		4.00%				4.00%
Tier 1 (to risk-weighted assets), Well-capitalized minimum		6.00%				6.00%
Total (to risk-weighted assets), Amount		20,887,000,000	21,669,000,000			15,587,000,000	14,827,000,000
Total (to risk-weighted assets), Ratio		16.40%	14.07%			18.69%	17.06%
Total (to risk-weighted assets), Required minimum		8.00%				8.00%
Total (to risk-weighted assets), Well-capitalized minimum		10.00%				10.00%
Tier 1 leverage (to adjusted average assets), Amount		19,571,000,000	20,232,000,000			14,926,000,000	14,136,000,000
Tier 1 leverage (to adjusted average assets), Ratio		13.16%	11.16%			16.33%	15.30%
Tier One Leverage Capital Required for Capital Adequacy to Average Assets				3.00%	4.00%
Tier 1 Leverage To Average Assets For Ally Bank						15.00%
Tier 1 leverage (to adjusted average assets), Well-capitalized minimum						5.00%
Tier 1 common (to risk-weighted assets), Amount		$ 10,087,000,000	$ 10,749,000,000
Tier 1 common (to risk-weighted assets), Ratio		7.92%	6.98%