Summary Of Significant Accounting Policies	6 Months Ended
Jun. 30, 2013
Accounting Policies [Abstract]
Summary Of Significant Accounting Policies	Basis of Presentation The consolidated financial statements include our accounts and the accounts of our wholly-owned subsidiaries, including certain special-purpose financing entities utilized in secured financing transactions, which are considered variable interest entities ("VIEs"). All intercompany transactions and accounts have been eliminated in consolidation. The interim period consolidated financial statements, including the notes thereto, are condensed and do not include all disclosures required by generally accepted accounting principles ("GAAP") in the United States of America. These interim period financial statements should be read in conjunction with our consolidated financial statements that are included in the Annual Report on Form 10-K filed on February 15, 2013. The consolidated financial statements as of June 30, 2013, and for the three and six months ended June 30, 2013 and 2012, are unaudited and, in management’s opinion, include all adjustments, consisting of normal recurring adjustments, necessary for a fair presentation of the results for such interim periods. The results for interim periods are not necessarily indicative of results for a full year. The preparation of financial statements in conformity with GAAP in the United States of America requires management to make estimates and assumptions which affect the reported amounts of assets and liabilities and the disclosures of contingent assets and liabilities as of the date of the financial statements and the amount of revenue and costs and expenses during the reporting periods. Actual results could differ from those estimates and those differences may be material. These estimates include, among other things, the determination of the allowance for loan losses on finance receivables, estimated recovery value on leased vehicles, goodwill, income taxes and the expected cash flows on pre-acquisition consumer finance receivables. In addition, certain assumptions and judgments were used in the estimated fair value recorded for the international operations acquisition. See Note 2 - "Acquisition of Ally Financial Inc. International Operations" for further discussion. Generally, the financial statements of entities that operate outside of the United States are measured using the local currency as the functional currency. All assets and liabilities of the foreign subsidiaries are translated into U.S. dollars at period end exchange rates and the results of operations and cash flows are determined using approximate weighted average exchange rates for the period. Translation adjustments are related to the foreign subsidiaries using local currency as their functional currency and are reported as a separate component of accumulated other comprehensive loss. Foreign currency transaction gains or losses are recorded directly to the Consolidated Statements of Income and Comprehensive Income, regardless of whether such amounts are realized or unrealized. We may elect to enter into foreign currency derivatives to mitigate our exposure to changes in foreign exchange rates. See Note 8 - "Derivative Financial Instruments" for further discussion. Prior year amounts for leased vehicle income have been reclassified to conform to the current year presentation. Leased vehicle income is now presented separately on the consolidated statements of income and comprehensive income. It was previously incorrectly included in other income. Due to the financial statement impact of the international operations acquisition, the presentation convention has been changed from "thousands" to "millions" to simplify the review and analysis of our financial information. Some prior period amounts may not round under the new convention in a manner consistent with our previous presentation. In addition, we changed the presentation of debt on the consolidated balance sheets to better classify the debt facilities acquired with the international operations. Debt was previously presented in the following captions: credit facilities, securitization notes payable and senior notes, which were the only types of debt we held. The characteristics of the debt acquired with the international operations are more varied; therefore we simplified the presentation of our debt as secured and unsecured. Finance Receivables Our finance receivables are reported in two portfolios: pre-acquisition and post-acquisition. The pre-acquisition finance receivables are composed of (i) finance receivables originated in North America prior to the October 1, 2010 merger with General Motors Company (“GM”), all of which were considered to have had deterioration in credit quality, and (ii) finance receivables that were considered to have had deterioration in credit quality that were acquired with the international operations. The pre-acquisition portfolio will decrease over time with the amortization of the acquired receivables. The post-acquisition finance receivables are composed of (i) finance receivables originated in North America since the merger with GM, (ii) finance receivables originated in the international operations since the applicable acquisition dates and (iii) finance receivables that were considered to have had no deterioration in credit quality that were acquired with the international operations. The post-acquisition portfolio is expected to grow over time as we originate new receivables. Pre-Acquisition Finance Receivables Following the merger with GM and the acquisition of the international operations, we further divided the pre-acquisition finance receivables into multiple pools based on common risk characteristics. Through acquisition accounting adjustments, the allowance for loan losses that existed at the merger and the acquisition dates was eliminated and the receivables were adjusted to fair value. The pre-acquisition finance receivables were acquired at a discount, which contains two components: a non-accretable difference and an accretable yield. A non-accretable difference is the excess of contractually required payments (undiscounted amount of all uncollected contractual principal and interest payments, both past due and scheduled for the future) over the amount of cash flows, considering the impact of defaults and prepayments, expected to be collected. An accretable yield is the excess of the cash flows, considering the impact of defaults and prepayments, expected to be collected over the initial investment in the loans, which at the acquisition date was fair value. The accretable yield is recorded as finance charge income over the life of the acquired receivables. Any deterioration in the performance of the pre-acquisition finance receivables from their expected performance will result in an incremental provision for loan losses. Improvements in the performance of the pre-acquisition finance receivables which results in a significant increase in actual or expected cash flows will result first in the reversal of any incremental related allowance for loan losses and then in a transfer of the excess from the non-accretable difference to accretable yield, which will be recorded as finance charge income over the remaining life of the receivables. Once a pool of loans is assembled, the integrity of the pool is maintained. A loan is removed from a pool only if it is sold (other than to a consolidated VIE), paid in full, or written off. Our policy is to remove a loan individually from a pool based on comparing any amount received upon disposition of the loan or underlying collateral with the contractual amount remaining due. The excess of the contractual amount remaining due over the amount received upon its disposition is absorbed by the non-accretable difference. This removal method assumes that the amount received approximates pool performance expectations. The remaining accretable yield balance is unaffected and any material change in remaining effective yield caused by this removal method is addressed by our quarterly cash flow evaluation process for each pool. For loans that are resolved by payment in full, there is no reduction in the amount of non-accretable difference for the pool because there is no difference between the amount received and the contractual amount of the loan. Post-Acquisition Finance Receivables and Allowance for Loan Losses Finance receivables originated in North America since our October 1, 2010 merger with GM and in the international operations since the applicable acquisition dates are carried at amortized cost, net of allowance for loan losses. Provisions for loan losses are charged to operations in amounts sufficient to maintain the allowance for loan losses at levels considered adequate to cover probable credit losses inherent in our finance receivables. The allowance for loan losses on consumer finance receivables is established systematically based on the determination of the amount of probable credit losses inherent in the finance receivables as of the balance sheet date. We review charge-off experience factors, delinquency reports, historical collection rates, estimates of the value of the underlying collateral, economic trends, such as unemployment rates, and other information in order to make the necessary judgments as to the probable credit losses. We also use historical charge-off experience to determine the loss confirmation period, which is defined as the time between when an event, such as delinquency status, giving rise to a probable credit loss occurs with respect to a specific account and when such account is charged off. This loss confirmation period is applied to the forecasted probable credit losses to determine the amount of losses inherent in finance receivables at the balance sheet date. Assumptions regarding credit losses and loss confirmation periods are reviewed periodically and may be impacted by actual performance of finance receivables and changes in any of the factors discussed above. Should the credit loss assumption or loss confirmation period increase, there would be an increase in the amount of allowance for loan losses required, which would decrease the net carrying value of finance receivables and increase the amount of provision for loan losses. For the finance receivables acquired with the international operations that were considered to have no deterioration in credit quality, the existing allowance for loan losses was eliminated and the receivables were adjusted to fair value. The purchase discount will accrete to income over the life of the receivables, based on the interest method. Provisions for loan losses are charged to operations in amounts equal to net credit losses for the period. Any deterioration in the performance of the acquired receivables will result in an incremental provision for loan losses. Geographic Scope of Operations and Segment Information We conduct our financing operations directly and indirectly through our subsidiaries and affiliates. We offer substantially similar products and services throughout many different regions, subject to local regulations and market conditions. We report our business segments based on geographic regions: North America ("North America Segment") and International ("International Segment"). The North America Segment includes our operations in the United States and Canada. The International Segment includes our operations in all other countries. For additional financial information regarding our operations by business segments and operations by geographic regions, see Note 13 - "Segment Reporting". Related Party Transactions We offer loan and lease finance products through GM-franchised dealers to consumers purchasing new and certain used vehicles manufactured by GM and make commercial loans directly to GM-franchised dealers. GM makes cash payments to us for offering incentivized rates and structures on loan and lease finance products and makes payments to us to cover certain interest payments on commercial loans under subvention programs. At June 30, 2013 and December 31, 2012, we had intercompany receivables from GM in the amount of $105 million and $21 million under various programs. In addition, we had $57 million and $46 million due at June 30, 2013 and December 31, 2012, in outstanding loans to dealers that are consolidated by GM, in connection with our commercial lending program. Our international operations also provide financing to certain GM subsidiaries through factoring and other wholesale financing arrangements. As of June 30, 2013, $570 million was outstanding under such arrangements, and is included in commercial finance receivables. At June 30, 2013, we also have $379 million of related party payables due to GM, primarily for commercial finance receivables originated but not yet funded. These payables typically settle within 30 days. We have a $600 million line of credit with GM ("GM Related Party Credit Facility"). There were no advances outstanding under the GM Related Party Credit Facility at June 30, 2013 and December 31, 2012. Recent Accounting Pronouncements In February 2013, ASU ("2013-02"), Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income, was issued effective for annual and interim reporting periods beginning after December 15, 2012. The adoption of 2013-02 improves the reporting of reclassifications out of accumulated other comprehensive income. We adopted this ASU effective January 1, 2013, and the adoption did not have an impact on our consolidated financial position, results of operations and cash flows.

Basis of Presentation

The consolidated financial statements include our accounts and the accounts of our wholly-owned subsidiaries, including certain special-purpose financing entities utilized in secured financing transactions, which are considered variable interest entities ("VIEs"). All intercompany transactions and accounts have been eliminated in consolidation.

The interim period consolidated financial statements, including the notes thereto, are condensed and do not include all disclosures required by generally accepted accounting principles ("GAAP") in the United States of America. These interim period financial statements should be read in conjunction with our consolidated financial statements that are included in the Annual Report on Form 10-K filed on February 15, 2013.

The consolidated financial statements as of June 30, 2013, and for the three and six months ended June 30, 2013 and 2012, are unaudited and, in management’s opinion, include all adjustments, consisting of normal recurring adjustments, necessary for a fair presentation of the results for such interim periods. The results for interim periods are not necessarily indicative of results for a full year.

The preparation of financial statements in conformity with GAAP in the United States of America requires management to make estimates and assumptions which affect the reported amounts of assets and liabilities and the disclosures of contingent assets and liabilities as of the date of the financial statements and the amount of revenue and costs and expenses during the reporting periods. Actual results could differ from those estimates and those differences may be material. These estimates include, among other things, the determination of the allowance for loan losses on finance receivables, estimated recovery value on leased vehicles, goodwill, income taxes and the expected cash flows on pre-acquisition consumer finance receivables. In addition, certain assumptions and judgments were used in the estimated fair value recorded for the international operations acquisition. See Note 2 - "Acquisition of Ally Financial Inc. International Operations" for further discussion.

Generally, the financial statements of entities that operate outside of the United States are measured using the local currency as the functional currency. All assets and liabilities of the foreign subsidiaries are translated into U.S. dollars at period end exchange rates and the results of operations and cash flows are determined using approximate weighted average exchange rates for the period. Translation adjustments are related to the foreign subsidiaries using local currency as their functional currency and are reported as a separate component of accumulated other comprehensive loss. Foreign currency transaction gains or losses are recorded directly to the Consolidated Statements of Income and Comprehensive Income, regardless of whether such amounts are realized or unrealized. We may elect to enter into foreign currency derivatives to mitigate our exposure to changes in foreign exchange rates. See Note 8 - "Derivative Financial Instruments" for further discussion.

Prior year amounts for leased vehicle income have been reclassified to conform to the current year presentation. Leased vehicle income is now presented separately on the consolidated statements of income and comprehensive income. It was previously incorrectly included in other income.

Due to the financial statement impact of the international operations acquisition, the presentation convention has been changed from "thousands" to "millions" to simplify the review and analysis of our financial information. Some prior period amounts may not round under the new convention in a manner consistent with our previous presentation. In addition, we changed the presentation of debt on the consolidated balance sheets to better classify the debt facilities acquired with the international operations. Debt was previously presented in the following captions: credit facilities, securitization notes payable and senior notes, which were the only types of debt we held. The characteristics of the debt acquired with the international operations are more varied; therefore we simplified the presentation of our debt as secured and unsecured.

Finance Receivables

Our finance receivables are reported in two portfolios: pre-acquisition and post-acquisition. The pre-acquisition finance receivables are composed of (i) finance receivables originated in North America prior to the October 1, 2010 merger with General Motors Company (“GM”), all of which were considered to have had deterioration in credit quality, and (ii) finance receivables that were considered to have had deterioration in credit quality that were acquired with the international operations. The pre-acquisition portfolio will decrease over time with the amortization of the acquired receivables.

The post-acquisition finance receivables are composed of (i) finance receivables originated in North America since the merger with GM, (ii) finance receivables originated in the international operations since the applicable acquisition dates and (iii) finance receivables that were considered to have had no deterioration in credit quality that were acquired with the international operations. The post-acquisition portfolio is expected to grow over time as we originate new receivables.

Pre-Acquisition Finance Receivables

Following the merger with GM and the acquisition of the international operations, we further divided the pre-acquisition finance receivables into multiple pools based on common risk characteristics. Through acquisition accounting adjustments, the allowance for loan losses that existed at the merger and the acquisition dates was eliminated and the receivables were adjusted to fair value. The pre-acquisition finance receivables were acquired at a discount, which contains two components: a non-accretable difference and an accretable yield. A non-accretable difference is the excess of contractually required payments (undiscounted amount of all uncollected contractual principal and interest payments, both past due and scheduled for the future) over the amount of cash flows, considering the impact of defaults and prepayments, expected to be collected. An accretable yield is the excess of the cash flows, considering the impact of defaults and prepayments, expected to be collected over the initial investment in the loans, which at the acquisition date was fair value. The accretable yield is recorded as finance charge income over the life of the acquired receivables.

Any deterioration in the performance of the pre-acquisition finance receivables from their expected performance will result in an incremental provision for loan losses. Improvements in the performance of the pre-acquisition finance receivables which results in a significant increase in actual or expected cash flows will result first in the reversal of any incremental related allowance for loan losses and then in a transfer of the excess from the non-accretable difference to accretable yield, which will be recorded as finance charge income over the remaining life of the receivables.

Once a pool of loans is assembled, the integrity of the pool is maintained. A loan is removed from a pool only if it is sold (other than to a consolidated VIE), paid in full, or written off. Our policy is to remove a loan individually from a pool based on comparing any amount received upon disposition of the loan or underlying collateral with the contractual amount remaining due. The excess of the contractual amount remaining due over the amount received upon its disposition is absorbed by the non-accretable difference. This removal method assumes that the amount received approximates pool performance expectations. The remaining accretable yield balance is unaffected and any material change in remaining effective yield caused by this removal method is addressed by our quarterly cash flow evaluation process for each pool. For loans that are resolved by payment in full, there is no reduction in the amount of non-accretable difference for the pool because there is no difference between the amount received and the contractual amount of the loan.

Post-Acquisition Finance Receivables and Allowance for Loan Losses

Finance receivables originated in North America since our October 1, 2010 merger with GM and in the international operations since the applicable acquisition dates are carried at amortized cost, net of allowance for loan losses. Provisions for loan losses are charged to operations in amounts sufficient to maintain the allowance for loan losses at levels considered adequate to cover probable credit losses inherent in our finance receivables.

The allowance for loan losses on consumer finance receivables is established systematically based on the determination of the amount of probable credit losses inherent in the finance receivables as of the balance sheet date. We review charge-off experience factors, delinquency reports, historical collection rates, estimates of the value of the underlying collateral, economic trends, such as unemployment rates, and other information in order to make the necessary judgments as to the probable credit losses. We also use historical charge-off experience to determine the loss confirmation period, which is defined as the time between when an event, such as delinquency status, giving rise to a probable credit loss occurs with respect to a specific account and when such account is charged off. This loss confirmation period is applied to the forecasted probable credit losses to determine the amount of losses inherent in finance receivables at the balance sheet date. Assumptions regarding credit losses and loss confirmation periods are reviewed periodically and may be impacted by actual performance of finance receivables and changes in any of the factors discussed above. Should the credit loss assumption or loss confirmation period increase, there would be an increase in the amount of allowance for loan losses required, which would decrease the net carrying value of finance receivables and increase the amount of provision for loan losses.

For the finance receivables acquired with the international operations that were considered to have no deterioration in credit quality, the existing allowance for loan losses was eliminated and the receivables were adjusted to fair value. The purchase discount will accrete to income over the life of the receivables, based on the interest method. Provisions for loan losses are charged to operations in amounts equal to net credit losses for the period. Any deterioration in the performance of the acquired receivables will result in an incremental provision for loan losses.

Geographic Scope of Operations and Segment Information

We conduct our financing operations directly and indirectly through our subsidiaries and affiliates. We offer substantially similar products and services throughout many different regions, subject to local regulations and market conditions. We report our business segments based on geographic regions: North America ("North America Segment") and International ("International Segment"). The North America Segment includes our operations in the United States and Canada. The International Segment includes our operations in all other countries. For additional financial information regarding our operations by business segments and operations by geographic regions, see Note 13 - "Segment Reporting".

Related Party Transactions

We offer loan and lease finance products through GM-franchised dealers to consumers purchasing new and certain used vehicles manufactured by GM and make commercial loans directly to GM-franchised dealers. GM makes cash payments to us for offering incentivized rates and structures on loan and lease finance products and makes payments to us to cover certain interest payments on commercial loans under subvention programs. At June 30, 2013 and December 31, 2012, we had intercompany receivables from GM in the amount of $105 million and $21 million under various programs.

In addition, we had $57 million and $46 million due at June 30, 2013 and December 31, 2012, in outstanding loans to dealers that are consolidated by GM, in connection with our commercial lending program. Our international operations also provide financing to certain GM subsidiaries through factoring and other wholesale financing arrangements. As of June 30, 2013, $570 million was outstanding under such arrangements, and is included in commercial finance receivables. At June 30, 2013, we also have $379 million of related party payables due to GM, primarily for commercial finance receivables originated but not yet funded. These payables typically settle within 30 days.

We have a $600 million line of credit with GM ("GM Related Party Credit Facility"). There were no advances outstanding under the GM Related Party Credit Facility at June 30, 2013 and December 31, 2012.

Recent Accounting Pronouncements

In February 2013, ASU ("2013-02"), Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income, was issued effective for annual and interim reporting periods beginning after December 15, 2012. The adoption of 2013-02 improves the reporting of reclassifications out of accumulated other comprehensive income. We adopted this ASU effective January 1, 2013, and the adoption did not have an impact on our consolidated financial position, results of operations and cash flows.