Nature of Business and Basis of Presentation	3 Months Ended
Mar. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Business and Basis of Presentation	1. Nature of Business and Basis of Presentation Nature of Business Mr. Cooper Group Inc., collectively with its consolidated subsidiaries, (“Mr. Cooper”, the “Company”, “we”, “us” or “our”) provides servicing, origination and transaction-based services related to single family residences throughout the United States with operations under its primary brands: Mr. Cooper® and Xome®. Mr. Cooper is one of the largest home loan originators and servicers in the country focused on delivering a variety of servicing and lending products, services and technologies. Xome provides real estate data as well as a range of services including real estate brokerage, title, closing, valuation and field services to lenders, investors and consumers. The Company’s corporate website is located at www.mrcoopergroup.com. The Company has provided a glossary of terms, which defines certain industry-specific and other terms that are used herein, in the MD&A section of this Form 10-Q. Mr. Cooper, which was previously known as WMIH Corp. (“WMIH”), is a corporation duly organized and existing under the laws of the State of Delaware since May 11, 2015. On July 31, 2018, Wand Merger Corporation (“Merger Sub”), a wholly-owned subsidiary of WMIH merged with and into Nationstar Mortgage Holdings Inc. (“Nationstar”), with Nationstar continuing as a wholly-owned subsidiary of WMIH (the “Merger”). Prior to the Merger, WMIH had limited operations other than its reinsurance business that operated in runoff mode. As a result of the Merger, shares of Nationstar common stock were delisted from the New York Stock Exchange. Following the Merger closing, the combined company traded on NASDAQ under the ticker symbol “WMIH” until October 10, 2018, when WMIH changed its name to “Mr. Cooper Group Inc.” and its ticker symbol to “COOP”. Basis of Presentation The consolidated interim financial statements of the Company have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) for interim financial information and in accordance with the instructions to Form 10-Q and Article 10 of Regulation S-X as promulgated by the SEC. Accordingly, the financial statements do not include all of the information and footnotes required by GAAP for complete financial statements and should be read in conjunction with the audited consolidated financial statements and notes thereto included in the Company’s Annual Reports on Form 10-K for the year ended December 31, 2019. The interim consolidated financial statements are unaudited; however, in the opinion of management, all adjustments, consisting of normal recurring items, considered necessary for a fair presentation of the results of the interim periods have been included. Dollar amounts are reported in millions, except per share data and other key metrics, unless otherwise noted. The Company evaluated subsequent events through the date these interim consolidated financial statements were issued. Basis of Consolidation The consolidated financial statements include the accounts of the Company, its wholly-owned subsidiaries, other entities in which the Company has a controlling financial interest and those variable interest entities (“VIE”) where the Company’s wholly-owned subsidiaries are the primary beneficiaries. Assets and liabilities of VIEs and their respective results of operations are consolidated from the date that the Company became the primary beneficiary through the date the Company ceases to be the primary beneficiary. The Company applies the equity method of accounting to investments where it is able to exercise significant influence, but not control, over the policies and procedures of the entity and owns less than 50% of the voting interests. Investments in certain companies over which the Company does not exert significant influence are accounted for as cost method investments. Intercompany balances and transactions on consolidated entities have been eliminated. Business combinations are included in the consolidated financial statements from their respective dates of acquisition. Use of Estimates The preparation of the consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. Actual results could differ from these estimates due to factors such as adverse changes in the economy, changes in interest rates, secondary market pricing for loans held for sale and derivatives, strength of underwriting and servicing practices, changes in prepayment assumptions, declines in home prices or discrete events adversely affecting specific borrowers, and such differences could be material. Recent Accounting Guidance Adopted Accounting Standards Update No. 2016-13, Financial Instruments - Credit Losses (Topic 326), (“ASU 2016-13”) requires expected credit losses for financial instruments held at the reporting date to be measured based on historical experience, current conditions and reasonable and supportable forecasts, which is referred to as the current expected credit loss (“CECL”) methodology. The update eliminates the initial recognition of credit losses on an incurred basis in current GAAP and instead reflects an entity’s current estimate of all expected credit losses over the life of the asset. Previously, when credit losses were measured under GAAP, an entity generally only considered past events and current conditions in measuring the incurred loss. The new standard will reflect management’s best estimate of all expected credit losses for the Company’s financial assets that are recognized at amortized cost. The guidance is effective for the Company as of January 1, 2020, with a cumulative-effect adjustment to retained earnings as of that date. Based upon management’s scoping analysis, the Company determined that reverse mortgage interests, net of reserves, advances and other receivables, net of reserves, and certain financial instruments included in other assets are within the scope of ASU 2016-13. Certain financial instruments within these respective line items have been determined to have limited expected credit-related losses due to the contractual servicing agreements with agencies and loan product guarantees. For advances and other receivables, net, the Company determined that the majority of estimated losses are due to servicing operational errors and credit-related losses are not significant because of the contractual relationships with the agencies. For reverse mortgage interests the Company determined that the guarantee from Federal Housing Administration (“FHA”) on Home Equity Conversion Mortgage (“HECM“) loan products limits credit-related losses to an immaterial amount with substantially all losses related to servicing operational errors. For other assets, primarily trade receivables, the Company determined that these are short-term in nature (less than one year), and the estimated credit-related losses over the life of these receivables are similar to those resulting from the Company’s existing loss reserve process. For each of the aforementioned financial instruments carried at amortized cost, the Company enhanced its processes to consider and include the requirements of ASU 2016-13, as applicable, into the determination of credit-related losses. On January 1, 2020, the Company adopted ASU 2016-13 using the modified retrospective method for the above-mentioned financial assets. Results for reporting periods after January 1, 2020 are presented under ASU 2016-13 while prior period amounts continue to be reported in accordance with previously applicable GAAP. The Company recorded transition adjustments aggregating to a net increase of $9, or $7 after tax, to retained earnings and a reduction of $7 to the advances and other receivables reserve and a $2 reduction in the other assets reserves, as of January 1, 2020 for the cumulative effect of adopting ASU 2016-13. In connection with adoption of ASU 2016-13, the Company updated its accounting policies as follows: For certain financial instruments included in advances and other receivables, net and certain trade receivables and accrued revenues included in other assets that within the scope of ASU 2016-13, the reserve methodology was revised to consider CECL losses. The revised CECL methodology considers expected lifetime loss rates calculated from historical data using a weighted average life to determine the current expected credit loss required. Due to the nature of the financial instrument, reverse mortgage interests, net of reserves, had limited impact from the adoption of CECL to the reserve methodology. See Note 4, Advances and Other Receivables, Net, Note 5, Reverse Mortgage Interests, Net, and Note 8, Other Assets, for additional information. Factors that influenced management’s current estimate of expected credit losses for certain advances and other receivables and certain trade receivables and accrued revenues included the following: historical collection and loss rates, passage of time, weighted average life of receivables, various qualitative factors including current economic conditions. Factors that influenced management’s current estimate of expected credit related losses for certain reverse mortgage interests included the following: historical collection and loss rates, foreclosure timelines, and values of underlying collateral. Accounting Standards Update No. 2018-13, Fair Value Measurement (Topic 820) - Changes to the Disclosure Requirements for Fair Value Measurement, (“ASU 2018-13”) removes the requirement to disclose the amount of and reasons for transfers between Level 1 and Level 2 fair value measurement methodologies, the policy for timing of transfers between levels and the valuation processes for Level 3 fair value measurements. It also adds a requirement to disclose changes in unrealized gains and losses for the period included in other comprehensive income for recurring Level 3 fair value measurements held at the end of the reporting period and the range and weighted average of significant unobservable inputs used to develop Level 3 measurements. For certain unobservable inputs, entities may disclose other quantitative information in lieu of the weighted average if the other quantitative information would be a more reasonable and rational method to reflect the distribution of unobservable inputs used to develop Level 3 fair value measurements. The Company adopted ASU 2018-13 on January 1, 2020. The guidance does not have a material impact to the disclosures currently provided by the Company.

1. Nature of Business and Basis of Presentation

Nature of Business

Mr. Cooper Group Inc., collectively with its consolidated subsidiaries, (“Mr. Cooper”, the “Company”, “we”, “us” or “our”) provides servicing, origination and transaction-based services related to single family residences throughout the United States with operations under its primary brands: Mr. Cooper® and Xome®. Mr. Cooper is one of the largest home loan originators and servicers in the country focused on delivering a variety of servicing and lending products, services and technologies. Xome provides real estate data as well as a range of services including real estate brokerage, title, closing, valuation and field services to lenders, investors and consumers. The Company’s corporate website is located at www.mrcoopergroup.com. The Company has provided a glossary of terms, which defines certain industry-specific and other terms that are used herein, in the MD&A section of this Form 10-Q.

Mr. Cooper, which was previously known as WMIH Corp. (“WMIH”), is a corporation duly organized and existing under the laws of the State of Delaware since May 11, 2015. On July 31, 2018, Wand Merger Corporation (“Merger Sub”), a wholly-owned subsidiary of WMIH merged with and into Nationstar Mortgage Holdings Inc. (“Nationstar”), with Nationstar continuing as a wholly-owned subsidiary of WMIH (the “Merger”). Prior to the Merger, WMIH had limited operations other than its reinsurance business that operated in runoff mode. As a result of the Merger, shares of Nationstar common stock were delisted from the New York Stock Exchange. Following the Merger closing, the combined company traded on NASDAQ under the ticker symbol “WMIH” until October 10, 2018, when WMIH changed its name to “Mr. Cooper Group Inc.” and its ticker symbol to “COOP”.

Basis of Presentation

The consolidated interim financial statements of the Company have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) for interim financial information and in accordance with the instructions to Form 10-Q and Article 10 of Regulation S-X as promulgated by the SEC. Accordingly, the financial statements do not include all of the information and footnotes required by GAAP for complete financial statements and should be read in conjunction with the audited consolidated financial statements and notes thereto included in the Company’s Annual Reports on Form 10-K for the year ended December 31, 2019.

The interim consolidated financial statements are unaudited; however, in the opinion of management, all adjustments, consisting of normal recurring items, considered necessary for a fair presentation of the results of the interim periods have been included. Dollar amounts are reported in millions, except per share data and other key metrics, unless otherwise noted.

The Company evaluated subsequent events through the date these interim consolidated financial statements were issued.

Basis of Consolidation

The consolidated financial statements include the accounts of the Company, its wholly-owned subsidiaries, other entities in which the Company has a controlling financial interest and those variable interest entities (“VIE”) where the Company’s wholly-owned subsidiaries are the primary beneficiaries. Assets and liabilities of VIEs and their respective results of operations are consolidated from the date that the Company became the primary beneficiary through the date the Company ceases to be the primary beneficiary. The Company applies the equity method of accounting to investments where it is able to exercise significant influence, but not control, over the policies and procedures of the entity and owns less than 50% of the voting interests. Investments in certain companies over which the Company does not exert significant influence are accounted for as cost method investments. Intercompany balances and transactions on consolidated entities have been eliminated. Business combinations are included in the consolidated financial statements from their respective dates of acquisition.

Use of Estimates

The preparation of the consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. Actual results could differ from these estimates due to factors such as adverse changes in the economy, changes in interest rates, secondary market pricing for loans held for sale and derivatives, strength of underwriting and servicing practices, changes in prepayment assumptions, declines in home prices or discrete events adversely affecting specific borrowers, and such differences could be material.

Recent Accounting Guidance Adopted

Accounting Standards Update No. 2016-13, Financial Instruments - Credit Losses (Topic 326), (“ASU 2016-13”) requires expected credit losses for financial instruments held at the reporting date to be measured based on historical experience, current conditions and reasonable and supportable forecasts, which is referred to as the current expected credit loss (“CECL”) methodology. The update eliminates the initial recognition of credit losses on an incurred basis in current GAAP and instead reflects an entity’s current estimate of all expected credit losses over the life of the asset. Previously, when credit losses were measured under GAAP, an entity generally only considered past events and current conditions in measuring the incurred loss. The new standard will reflect management’s best estimate of all expected credit losses for the Company’s financial assets that are recognized at amortized cost. The guidance is effective for the Company as of January 1, 2020, with a cumulative-effect adjustment to retained earnings as of that date.

Based upon management’s scoping analysis, the Company determined that reverse mortgage interests, net of reserves, advances and other receivables, net of reserves, and certain financial instruments included in other assets are within the scope of ASU 2016-13. Certain financial instruments within these respective line items have been determined to have limited expected credit-related losses due to the contractual servicing agreements with agencies and loan product guarantees. For advances and other receivables, net, the Company determined that the majority of estimated losses are due to servicing operational errors and credit-related losses are not significant because of the contractual relationships with the agencies. For reverse mortgage interests the Company determined that the guarantee from Federal Housing Administration (“FHA”) on Home Equity Conversion Mortgage (“HECM“) loan products limits credit-related losses to an immaterial amount with substantially all losses related to servicing operational errors. For other assets, primarily trade receivables, the Company determined that these are short-term in nature (less than one year), and the estimated credit-related losses over the life of these receivables are similar to those resulting from the Company’s existing loss reserve process. For each of the aforementioned financial instruments carried at amortized cost, the Company enhanced its processes to consider and include the requirements of ASU 2016-13, as applicable, into the determination of credit-related losses.

On January 1, 2020, the Company adopted ASU 2016-13 using the modified retrospective method for the above-mentioned financial assets. Results for reporting periods after January 1, 2020 are presented under ASU 2016-13 while prior period amounts continue to be reported in accordance with previously applicable GAAP. The Company recorded transition adjustments aggregating to a net increase of $9, or $7 after tax, to retained earnings and a reduction of $7 to the advances and other receivables reserve and a $2 reduction in the other assets reserves, as of January 1, 2020 for the cumulative effect of adopting ASU 2016-13.

In connection with adoption of ASU 2016-13, the Company updated its accounting policies as follows:

For certain financial instruments included in advances and other receivables, net and certain trade receivables and accrued revenues included in other assets that within the scope of ASU 2016-13, the reserve methodology was revised to consider CECL losses. The revised CECL methodology considers expected lifetime loss rates calculated from historical data using a weighted average life to determine the current expected credit loss required. Due to the nature of the financial instrument, reverse mortgage interests, net of reserves, had limited impact from the adoption of CECL to the reserve methodology. See Note 4, Advances and Other Receivables, Net, Note 5, Reverse Mortgage Interests, Net, and Note 8, Other Assets, for additional information.

Factors that influenced management’s current estimate of expected credit losses for certain advances and other receivables and certain trade receivables and accrued revenues included the following: historical collection and loss rates, passage of time, weighted average life of receivables, various qualitative factors including current economic conditions.

Factors that influenced management’s current estimate of expected credit related losses for certain reverse mortgage interests included the following: historical collection and loss rates, foreclosure timelines, and values of underlying collateral.

Accounting Standards Update No. 2018-13, Fair Value Measurement (Topic 820) - Changes to the Disclosure Requirements for Fair Value Measurement, (“ASU 2018-13”) removes the requirement to disclose the amount of and reasons for transfers between Level 1 and Level 2 fair value measurement methodologies, the policy for timing of transfers between levels and the valuation processes for Level 3 fair value measurements. It also adds a requirement to disclose changes in unrealized gains and losses for the period included in other comprehensive income for recurring Level 3 fair value measurements held at the end of the reporting period and the range and weighted average of significant unobservable inputs used to develop Level 3 measurements. For certain unobservable inputs, entities may disclose other quantitative information in lieu of the weighted average if the other quantitative information would be a more reasonable and rational method to reflect the distribution of unobservable inputs used to develop Level 3 fair value measurements. The Company adopted ASU 2018-13 on January 1, 2020. The guidance does not have a material impact to the disclosures currently provided by the Company.