Contingencies and Other Risks	9 Months Ended
Sep. 30, 2016
Loss Contingency [Abstract]
Contingencies Disclosure and Other Risks [Text Block]	Contingencies and Other Risks Legal Matters Ally and its subsidiaries, including Ally Bank, are or may be subject to potential liability in connection with pending or threatened legal proceedings and other matters. These legal matters may be formal or informal and include litigation and arbitration with one or more identified claimants, certified or purported class actions with yet-to-be-identified claimants, and regulatory or other governmental information-gathering requests, examinations, investigations, and enforcement proceedings. Our legal matters exist in varying stages of adjudication, arbitration, negotiation, or investigation and span our lines of business and operations. Claims may be based in law or equity—such as those arising under contracts or in tort and those involving banking, consumer-protection, securities, tax, employment, and other laws—and some can present novel legal theories and allege substantial or indeterminate damages. We accrue for a legal matter when a loss becomes probable and the amount of loss can be reasonably estimated. Accruals are evaluated each quarter and may be adjusted, upward or downward, based on our best judgment after consultation with counsel. No assurance exists that our accruals will not need to be adjusted in the future. The course and outcome of legal matters are inherently unpredictable. This is especially so when a matter is still in its early stages, the damages sought are indeterminate or unsupported, significant facts are unclear or disputed, novel questions of law or other meaningful legal uncertainties exist, a request to certify a proceeding as a class action is outstanding or granted, multiple parties are named, or regulatory or other governmental entities are involved. As a result, we cannot state with confidence how or when threatened or pending legal matters will be resolved and what losses may be incurred. Actual losses may be higher or lower than any amounts accrued for those matters, possibly to a significant degree. On the basis of information currently available, advice of counsel, available insurance coverage, and established reserves, it is the opinion of management that, except as described in the next paragraph, the eventual outcome of our existing legal matters will not have a material adverse effect on our consolidated financial condition, results of operations, or cash flows. It is possible, however, that an unfavorable resolution of legal matters may be material to our consolidated financial condition, results of operations, or cash flows in a particular period. Descriptions of our material legal matters follow. In each case, the matter could have material adverse consequences for us, including substantial damages or settlements, injunctions, governmental fines or penalties, and reputational or operational risks. We do not believe, however, that an estimate of reasonably possible losses or a range of reasonably possible losses in excess of established reserves—whether in excess of any related accrual or where no accrual exists—can be made for any of these matters, except as described within Indirect Automotive Finance Matters. Mortgage Matters We have received subpoenas from the U.S. Department of Justice (DOJ) that include a broad request for documentation and other information relating to residential mortgage-backed securities issued by our former mortgage subsidiary, Residential Capital, LLC and its subsidiaries (ResCap RMBS). In connection with these requests, the DOJ is investigating potential fraud and other potential legal claims related to ResCap RMBS, including its investigation of potential claims under the Financial Institutions Reform, Recovery, and Enforcement Act of 1989. The DOJ is also investigating potential claims under the False Claims Act (FCA) related to representations made by us in connection with investments in Ally made by the U.S. Department of the Treasury pursuant to the Troubled Asset Relief Program in 2008 and 2009 regarding certain claims against Residential Capital, LLC or its subsidiaries at that time. We have actively cooperated with the DOJ in connection with its investigations and potential claims. At the request of the DOJ, we entered into an agreement to voluntarily extend the statutes of limitations related to potential FCA claims, but this agreement expired at the end of January 2016. We are currently in advanced settlement discussions to resolve the DOJ’s investigations and potential claims. During the three months ended September 30, 2016, we established a reserve of $52 million within discontinued operations in connection with potential claims related to our discontinued mortgage business. Securities Litigation In October 2016, a purported class action—Bucks County Employees Retirement Fund v. Ally Financial Inc. et al, Case No. 16-013616-CZ—was filed in the Circuit Court for Wayne County in the State of Michigan. The complaint alleges material misstatements and omissions in connection with Ally’s initial public offering in April 2014, including a failure to adequately disclose the severity of rising subprime automotive loan delinquency rates, deficient underwriting measures employed in the origination of subprime automotive loans, and aggressive tactics used with low-income borrowers. The request for relief includes an indeterminate amount of damages, fees, and costs and other remedies. We intend to vigorously defend against this action. Automotive Subprime Matters In October 2014, we received a document request from the SEC in connection with its investigation related to subprime automotive finance and related securitization activities. Separately, in December 2014, we received a subpoena from the DOJ requesting similar information. In May 2015, we received an information request from the New York Department of Financial Services requesting similar information. We have cooperated with each of these agencies with respect to these matters. Indirect Automotive Finance Matters In December 2013, Ally Financial Inc. and Ally Bank entered into a Consent Order issued by the U.S. Consumer Financial Protection Bureau (CFPB) and a Consent Order jointly submitted with the DOJ and entered by the U.S. District Court for the Eastern District of Michigan (United States v. Ally Financial Inc. and Ally Bank, Civil Action No. 13-15180), in each case, pertaining to allegations of discrimination involving the automotive finance business. The Consent Orders require Ally to create a compliance plan addressing, at a minimum, the communication of Ally’s expectations of Equal Credit Opportunity Act (ECOA) compliance to our automotive dealer clients, maintenance of Ally’s existing limits on dealer finance income for contracts acquired by Ally, and monitoring for potential discrimination both at the dealer level and within our portfolio of contracts acquired across all of our automotive dealer clients. Ally formed a compliance committee consisting of certain Ally and Ally Bank directors to oversee Ally’s execution of the Consent Orders’ terms. Ally is required to meet certain stipulations under the Consent Orders, including a requirement to make monetary payments when ongoing remediation targets are not attained. Since 2013, Ally has expensed approximately $230 million for judgments, fines, and monetary remuneration payments to customers related to the Consent Orders. Ally expects to expense an additional $10 million to $15 million in the fourth quarter of 2016 for remaining monetary remuneration to customers related to the Consent Orders. The Consent Orders terminate, according to their terms, in 2017, and preclude the CFPB and the DOJ from pursuing any potential violations of the ECOA against Ally Financial Inc. or Ally Bank for conduct undertaken pursuant to the Consent Orders during the period of the Consent Orders. If the CFPB or the DOJ were to assert that Ally Financial Inc. or Ally Bank is violating the ECOA after the Consent Orders terminate, further legal proceedings could occur. Other Contingencies Ally and its subsidiaries, including Ally Bank, are or may be subject to potential liability under various other contingent exposures, including indemnification, tax, self-insurance, and other miscellaneous contingencies. We accrue for a contingent exposure when a loss becomes probable and the amount of loss can be reasonably estimated. Accruals are evaluated each quarter and may be adjusted, upward or downward, based on our best judgment. No assurance exists that our accruals will not need to be adjusted in the future, and actual losses may be higher or lower than any amounts accrued for those exposures, possibly to a significant degree. On the basis of information currently available, available insurance coverage, and established reserves, it is the opinion of management that the eventual outcome of our other contingent exposures will not have a material adverse effect on our consolidated financial condition, results of operations, or cash flows.

Contingencies and Other Risks

Legal Matters

Ally and its subsidiaries, including Ally Bank, are or may be subject to potential liability in connection with pending or threatened legal proceedings and other matters. These legal matters may be formal or informal and include litigation and arbitration with one or more identified claimants, certified or purported class actions with yet-to-be-identified claimants, and regulatory or other governmental information-gathering requests, examinations, investigations, and enforcement proceedings. Our legal matters exist in varying stages of adjudication, arbitration, negotiation, or investigation and span our lines of business and operations. Claims may be based in law or equity—such as those arising under contracts or in tort and those involving banking, consumer-protection, securities, tax, employment, and other laws—and some can present novel legal theories and allege substantial or indeterminate damages.

We accrue for a legal matter when a loss becomes probable and the amount of loss can be reasonably estimated. Accruals are evaluated each quarter and may be adjusted, upward or downward, based on our best judgment after consultation with counsel. No assurance exists that our accruals will not need to be adjusted in the future.

The course and outcome of legal matters are inherently unpredictable. This is especially so when a matter is still in its early stages, the damages sought are indeterminate or unsupported, significant facts are unclear or disputed, novel questions of law or other meaningful legal uncertainties exist, a request to certify a proceeding as a class action is outstanding or granted, multiple parties are named, or regulatory or other governmental entities are involved. As a result, we cannot state with confidence how or when threatened or pending legal matters will be resolved and what losses may be incurred. Actual losses may be higher or lower than any amounts accrued for those matters, possibly to a significant degree.

On the basis of information currently available, advice of counsel, available insurance coverage, and established reserves, it is the opinion of management that, except as described in the next paragraph, the eventual outcome of our existing legal matters will not have a material adverse effect on our consolidated financial condition, results of operations, or cash flows. It is possible, however, that an unfavorable resolution of legal matters may be material to our consolidated financial condition, results of operations, or cash flows in a particular period.

Descriptions of our material legal matters follow. In each case, the matter could have material adverse consequences for us, including substantial damages or settlements, injunctions, governmental fines or penalties, and reputational or operational risks. We do not believe, however, that an estimate of reasonably possible losses or a range of reasonably possible losses in excess of established reserves—whether in excess of any related accrual or where no accrual exists—can be made for any of these matters, except as described within Indirect Automotive Finance Matters.

Mortgage Matters

We have received subpoenas from the U.S. Department of Justice (DOJ) that include a broad request for documentation and other information relating to residential mortgage-backed securities issued by our former mortgage subsidiary, Residential Capital, LLC and its subsidiaries (ResCap RMBS). In connection with these requests, the DOJ is investigating potential fraud and other potential legal claims related to ResCap RMBS, including its investigation of potential claims under the Financial Institutions Reform, Recovery, and Enforcement Act of 1989. The DOJ is also investigating potential claims under the False Claims Act (FCA) related to representations made by us in connection with investments in Ally made by the U.S. Department of the Treasury pursuant to the Troubled Asset Relief Program in 2008 and 2009 regarding certain claims against Residential Capital, LLC or its subsidiaries at that time.

We have actively cooperated with the DOJ in connection with its investigations and potential claims. At the request of the DOJ, we entered into an agreement to voluntarily extend the statutes of limitations related to potential FCA claims, but this agreement expired at the end of January 2016. We are currently in advanced settlement discussions to resolve the DOJ’s investigations and potential claims.

During the three months ended September 30, 2016, we established a reserve of $52 million within discontinued operations in connection with potential claims related to our discontinued mortgage business.

Securities Litigation

In October 2016, a purported class action—Bucks County Employees Retirement Fund v. Ally Financial Inc. et al, Case No. 16-013616-CZ—was filed in the Circuit Court for Wayne County in the State of Michigan. The complaint alleges material misstatements and omissions in connection with Ally’s initial public offering in April 2014, including a failure to adequately disclose the severity of rising subprime automotive loan delinquency rates, deficient underwriting measures employed in the origination of subprime automotive loans, and aggressive tactics used with low-income borrowers. The request for relief includes an indeterminate amount of damages, fees, and costs and other remedies. We intend to vigorously defend against this action.

Automotive Subprime Matters

In October 2014, we received a document request from the SEC in connection with its investigation related to subprime automotive finance and related securitization activities. Separately, in December 2014, we received a subpoena from the DOJ requesting similar information. In May 2015, we received an information request from the New York Department of Financial Services requesting similar information. We have cooperated with each of these agencies with respect to these matters.

Indirect Automotive Finance Matters

In December 2013, Ally Financial Inc. and Ally Bank entered into a Consent Order issued by the U.S. Consumer Financial Protection Bureau (CFPB) and a Consent Order jointly submitted with the DOJ and entered by the U.S. District Court for the Eastern District of Michigan (United States v. Ally Financial Inc. and Ally Bank, Civil Action No. 13-15180), in each case, pertaining to allegations of discrimination involving the automotive finance business. The Consent Orders require Ally to create a compliance plan addressing, at a minimum, the communication of Ally’s expectations of Equal Credit Opportunity Act (ECOA) compliance to our automotive dealer clients, maintenance of Ally’s existing limits on dealer finance income for contracts acquired by Ally, and monitoring for potential discrimination both at the dealer level and within our portfolio of contracts acquired across all of our automotive dealer clients. Ally formed a compliance committee consisting of certain Ally and Ally Bank directors to oversee Ally’s execution of the Consent Orders’ terms. Ally is required to meet certain stipulations under the Consent Orders, including a requirement to make monetary payments when ongoing remediation targets are not attained.

Since 2013, Ally has expensed approximately $230 million for judgments, fines, and monetary remuneration payments to customers related to the Consent Orders. Ally expects to expense an additional $10 million to $15 million in the fourth quarter of 2016 for remaining monetary remuneration to customers related to the Consent Orders. The Consent Orders terminate, according to their terms, in 2017, and preclude the CFPB and the DOJ from pursuing any potential violations of the ECOA against Ally Financial Inc. or Ally Bank for conduct undertaken pursuant to the Consent Orders during the period of the Consent Orders. If the CFPB or the DOJ were to assert that Ally Financial Inc. or Ally Bank is violating the ECOA after the Consent Orders terminate, further legal proceedings could occur.

Other Contingencies

Ally and its subsidiaries, including Ally Bank, are or may be subject to potential liability under various other contingent exposures, including indemnification, tax, self-insurance, and other miscellaneous contingencies. We accrue for a contingent exposure when a loss becomes probable and the amount of loss can be reasonably estimated. Accruals are evaluated each quarter and may be adjusted, upward or downward, based on our best judgment. No assurance exists that our accruals will not need to be adjusted in the future, and actual losses may be higher or lower than any amounts accrued for those exposures, possibly to a significant degree. On the basis of information currently available, available insurance coverage, and established reserves, it is the opinion of management that the eventual outcome of our other contingent exposures will not have a material adverse effect on our consolidated financial condition, results of operations, or cash flows.