Description of Business and Significant Accounting Policies	6 Months Ended
Jun. 30, 2015
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Description of Business and Significant Accounting Policies	NOTE 1. DESCRIPTION OF BUSINESS AND SIGNIFICANT ACCOUNTING POLICIES Description of Business TriNet Group, Inc. (the Company or TriNet), a Delaware corporation incorporated in January 2000, provides a comprehensive human resources solution for small to medium-sized businesses. The Company’s solution includes payroll processing, human capital consulting, employment law compliance and employee benefits, including health insurance, retirement plans and workers compensation insurance. The Company provides its services through co-employment relationships with its customers, under which the Company and its customers each take responsibility for certain portions of the employer-employee relationship for worksite employees (WSEs). The Company is the employer of record for most administrative and regulatory purposes, including the following: (i) compensation through wages and salaries; (ii) employer payroll-related taxes payment; (iii) employee payroll-related taxes withholding and payment; (iv) employee benefit programs including health and life insurance, and others; and (v) workers compensation coverage. Segment Information The Company operates in one reportable segment in accordance with Accounting Standard Codification (ASC) 280 – Segment Reporting, issued by the Financial Accounting Standards Board (FASB). All of the Company’s service revenues are generated from external customers. Less than 1% of revenues is generated outside of the United States of America (U.S.). Substantially all of the Company’s long-lived assets are located in the U.S. Basis of Presentation The accompanying unaudited consolidated financial statements and footnotes thereto of the Company and its wholly owned subsidiaries have been prepared in accordance with U.S. generally accepted accounting principles (GAAP) and applicable rules and regulations of the Securities and Exchange Commission (SEC) regarding interim financial reporting. Certain information and note disclosures normally included in the financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. Therefore, these consolidated financial statements should be read in conjunction with the consolidated financial statements and notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2014, filed with the SEC on March 30, 2015. There have been no changes to the Company’s significant accounting policies described in such Annual Report that have had a material impact on its consolidated financial statements and related notes. All intercompany accounts and transactions have been eliminated in consolidation. The accompanying unaudited consolidated balance sheets present the current assets and current liabilities directly related to the processing of human resources transactions as WSE-related assets and WSE-related liabilities, respectively. WSE-related assets are comprised of cash and investments restricted for current workers compensation claim payments, payroll funds collected, accounts receivable, unbilled service revenues, and refundable or prepaid amounts related to the Company-sponsored workers compensation and health plan programs. WSE-related liabilities are comprised of customer prepayments, wages and payroll taxes accrued and payable, and liabilities related to the Company-sponsored workers compensation and health plan programs resulting from workers compensation case reserves, premium amounts due to providers for enrolled employees, and workers compensation and health reserves that are expected to be disbursed within the next 12 months. The unaudited interim financial statements have been prepared on the same basis as the annual financial statements and, in the opinion of management, reflect all adjustments, consisting only of normal recurring adjustments, necessary for fair presentation. The results of the six months ended June 30, 2015 are not necessarily indicative of the results to be expected for the year ending December 31, 2015. Seasonality and Insurance Variability Historically, the Company has experienced its highest monthly addition of WSEs, as well as its highest monthly levels of client attrition, in the month of January, primarily because clients that change their payroll service providers tend to do so at the beginning of a calendar year. In addition, the Company experiences higher levels of client attrition during the fourth quarter and, to a lesser extent, during the first quarter of the calendar year, in connection with renewals of the health insurance it provides for its WSEs, in the event that such renewals result in increased premiums that it passes on to its clients. The Company has also historically experienced higher insurance claim volumes in the second and third quarters of a fiscal year than in the first and fourth quarters of a fiscal year, as WSEs typically access their health care providers more often in the second and third quarters of a fiscal year, which has negatively impacted the Company’s insurance costs in these quarters. The Company has also experienced variability on a quarterly basis in the level of our insurance claims based on the unpredictable nature of large claims. These historical trends may change, and other seasonal trends and variability may develop that make it more difficult for the Company to manage its business. Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect certain reported amounts and disclosures. These estimates include, but are not limited to, allowances for accounts receivable, workers compensation related assets and liabilities, health plan assets and liabilities, recoverability of goodwill and other intangible assets, income taxes, stock-based compensation and other contingent liabilities. Such estimates are based on historical experience and on various other assumptions that Company management believes to be reasonable under the circumstances. Actual results could differ from those estimates. Recent Accounting Pronouncements In April 2015, the FASB issued Accounting Standards Update (ASU) 2015-05—Intangibles—Goodwill and Other—Internal-Use Software, as part of its initiative to reduce complexity in accounting standards (the Simplification Initiative). The amendment provides guidance to clarify the customer’s accounting for fees paid in a cloud computing arrangement. The amendment is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2015. Early adoption is permitted. The Company expects to adopt this guidance in 2016. The Company does not expect this guidance to have a material effect on its consolidated financial statements. In April 2015, the FASB issued ASU 2015-03— Interest—Imputation of Interest, as part of its Simplification Initiative. The amendment requires that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. The amendment is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2015. Early adoption is permitted for financial statements that have not been previously issued. The Company is currently evaluating the impact that the adoption of this guidance will have on its consolidated financial statements. In January 2015, the FASB issued ASU 2015-01— Income Statement-Extraordinary and Unusual Items, as part of its Simplification Initiative. ASU 2015-01 became effective on January 9, 2015. The amendment eliminates from GAAP the concept of extraordinary items. The amendment is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2015. A reporting entity may apply the amendments prospectively or retrospectively to all prior periods presented in the financial statements. Early adoption is permitted provided that the guidance is applied from the beginning of the fiscal year of adoption. The Company adopted this guidance in 2014. The adoption did not have an effect on the consolidated financial statements. In November 2014, the FASB issued ASU 2014-17— Business Combinations, which provides an acquired entity with an option to apply pushdown accounting in its financial statements upon occurrence of an event in which an acquirer obtains control of the acquired entity. ASU 2014-17 became effective on November 28, 2014. An acquired entity can make an election to apply the guidance to future change-in-control events or to its most recent change-in-control event. However, if the financial statements for the period in which the most recent change-in-control event occurred already have been issued or made available to be issued, the application of this guidance would be a change in accounting principle. The Company adopted this guidance in 2014. The adoption did not have an effect on the consolidated financial statements. In August 2014, the FASB issued ASU 2014-15—Presentation of Financial Statements — Going Concern (Subtopic 205-40), which addresses management’s responsibility to evaluate whether there is substantial doubt about an entity’s ability to continue as a going concern and to provide related footnote disclosures. Management’s evaluation should be based on relevant conditions and events that are known and reasonably knowable at the date that the financial statements are issued. The standard will be effective for the first interim period within annual reporting periods beginning after December 15, 2016. Early adoption is permitted. The Company does not expect to early adopt this guidance and does not believe that the adoption of this guidance will have a material effect on its consolidated financial statements. In June 2014, the FASB issued ASU 2014-12—Compensation - Stock Compensation, which requires that a performance target that affects vesting and that could be achieved after the requisite service period be treated as a performance condition. ASU 2014-12 is effective for annual reporting periods, and interim periods within those years, beginning after December 15, 2015. Early adoption is permitted. The amendments may be applied prospectively to all awards granted or modified after the effective date or retrospectively to all awards with performance targets that are outstanding as of the beginning of the earliest annual period presented. The Company does not expect this guidance to have a material effect on its consolidated financial statements. The Company expects to adopt this guidance in 2016. In May 2014, the FASB issued ASU 2014-09—Revenue from Contracts with Customers, which will replace most existing revenue recognition guidance under GAAP. The core principle of the guidance is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The standard provides a five-step analysis of transactions to determine when and how revenue is recognized. In July 2015, the FASB deferred the effective date to annual reporting periods, and interim periods within those years, beginning after December 15, 2017. Early adoption at the original effective date of December 15, 2016 is permitted. The amendments may be applied retrospectively or as a cumulative-effect adjustment as of the date of adoption. The Company has not yet selected a method of adoption and is currently evaluating the effect that the amendments will have on the consolidated financial statements.

NOTE 1. DESCRIPTION OF BUSINESS AND SIGNIFICANT ACCOUNTING POLICIES

Description of Business

TriNet Group, Inc. (the Company or TriNet), a Delaware corporation incorporated in January 2000, provides a comprehensive human resources solution for small to medium-sized businesses. The Company’s solution includes payroll processing, human capital consulting, employment law compliance and employee benefits, including health insurance, retirement plans and workers compensation insurance.

The Company provides its services through co-employment relationships with its customers, under which the Company and its customers each take responsibility for certain portions of the employer-employee relationship for worksite employees (WSEs). The Company is the employer of record for most administrative and regulatory purposes, including the following: (i) compensation through wages and salaries; (ii) employer payroll-related taxes payment; (iii) employee payroll-related taxes withholding and payment; (iv) employee benefit programs including health and life insurance, and others; and (v) workers compensation coverage.

Segment Information

The Company operates in one reportable segment in accordance with Accounting Standard Codification (ASC) 280 – Segment Reporting, issued by the Financial Accounting Standards Board (FASB). All of the Company’s service revenues are generated from external customers. Less than 1% of revenues is generated outside of the United States of America (U.S.). Substantially all of the Company’s long-lived assets are located in the U.S.

Basis of Presentation

The accompanying unaudited consolidated financial statements and footnotes thereto of the Company and its wholly owned subsidiaries have been prepared in accordance with U.S. generally accepted accounting principles (GAAP) and applicable rules and regulations of the Securities and Exchange Commission (SEC) regarding interim financial reporting. Certain information and note disclosures normally included in the financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. Therefore, these consolidated financial statements should be read in conjunction with the consolidated financial statements and notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2014, filed with the SEC on March 30, 2015. There have been no changes to the Company’s significant accounting policies described in such Annual Report that have had a material impact on its consolidated financial statements and related notes. All intercompany accounts and transactions have been eliminated in consolidation.

The accompanying unaudited consolidated balance sheets present the current assets and current liabilities directly related to the processing of human resources transactions as WSE-related assets and WSE-related liabilities, respectively. WSE-related assets are comprised of cash and investments restricted for current workers compensation claim payments, payroll funds collected, accounts receivable, unbilled service revenues, and refundable or prepaid amounts related to the Company-sponsored workers compensation and health plan programs. WSE-related liabilities are comprised of customer prepayments, wages and payroll taxes accrued and payable, and liabilities related to the Company-sponsored workers compensation and health plan programs resulting from workers compensation case reserves, premium amounts due to providers for enrolled employees, and workers compensation and health reserves that are expected to be disbursed within the next 12 months.

The unaudited interim financial statements have been prepared on the same basis as the annual financial statements and, in the opinion of management, reflect all adjustments, consisting only of normal recurring adjustments, necessary for fair presentation. The results of the six months ended June 30, 2015 are not necessarily indicative of the results to be expected for the year ending December 31, 2015.

Seasonality and Insurance Variability

Historically, the Company has experienced its highest monthly addition of WSEs, as well as its highest monthly levels of client attrition, in the month of January, primarily because clients that change their payroll service providers tend to do so at the beginning of a calendar year. In addition, the Company experiences higher levels of client attrition during the fourth quarter and, to a lesser extent, during the first quarter of the calendar year, in connection with renewals of the health insurance it provides for its WSEs, in the event that such renewals result in increased premiums that it passes on to its clients. The Company has also historically experienced higher insurance claim volumes in the second and third quarters of a fiscal year than in the first and fourth quarters of a fiscal year, as WSEs typically access their health care providers more often in the second and third quarters of a fiscal year, which has negatively impacted the Company’s insurance costs in these quarters. The Company has also experienced variability on a quarterly basis in the level of our insurance claims based on the unpredictable nature of large claims. These historical trends may change, and other seasonal trends and variability may develop that make it more difficult for the Company to manage its business.

Use of Estimates

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect certain reported amounts and disclosures. These estimates include, but are not limited to, allowances for accounts receivable, workers compensation related assets and liabilities, health plan assets and liabilities, recoverability of goodwill and other intangible assets, income taxes, stock-based compensation and other contingent liabilities. Such estimates are based on historical experience and on various other assumptions that Company management believes to be reasonable under the circumstances. Actual results could differ from those estimates.

Recent Accounting Pronouncements

In April 2015, the FASB issued Accounting Standards Update (ASU) 2015-05—Intangibles—Goodwill and Other—Internal-Use Software, as part of its initiative to reduce complexity in accounting standards (the Simplification Initiative). The amendment provides guidance to clarify the customer’s accounting for fees paid in a cloud computing arrangement. The amendment is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2015. Early adoption is permitted. The Company expects to adopt this guidance in 2016. The Company does not expect this guidance to have a material effect on its consolidated financial statements.

In April 2015, the FASB issued ASU 2015-03— Interest—Imputation of Interest, as part of its Simplification Initiative. The amendment requires that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. The amendment is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2015. Early adoption is permitted for financial statements that have not been previously issued. The Company is currently evaluating the impact that the adoption of this guidance will have on its consolidated financial statements.

In January 2015, the FASB issued ASU 2015-01— Income Statement-Extraordinary and Unusual Items, as part of its Simplification Initiative. ASU 2015-01 became effective on January 9, 2015. The amendment eliminates from GAAP the concept of extraordinary items. The amendment is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2015. A reporting entity may apply the amendments prospectively or retrospectively to all prior periods presented in the financial statements. Early adoption is permitted provided that the guidance is applied from the beginning of the fiscal year of adoption. The Company adopted this guidance in 2014. The adoption did not have an effect on the consolidated financial statements.

In November 2014, the FASB issued ASU 2014-17— Business Combinations, which provides an acquired entity with an option to apply pushdown accounting in its financial statements upon occurrence of an event in which an acquirer obtains control of the acquired entity. ASU 2014-17 became effective on November 28, 2014. An acquired entity can make an election to apply the guidance to future change-in-control events or to its most recent change-in-control event. However, if the financial statements for the period in which the most recent change-in-control event occurred already have been issued or made available to be issued, the application of this guidance would be a change in accounting principle. The Company adopted this guidance in 2014. The adoption did not have an effect on the consolidated financial statements.

In August 2014, the FASB issued ASU 2014-15—Presentation of Financial Statements — Going Concern (Subtopic 205-40), which addresses management’s responsibility to evaluate whether there is substantial doubt about an entity’s ability to continue as a going concern and to provide related footnote disclosures. Management’s evaluation should be based on relevant conditions and events that are known and reasonably knowable at the date that the financial statements are issued. The standard will be effective for the first interim period within annual reporting periods beginning after December 15, 2016. Early adoption is permitted. The Company does not expect to early adopt this guidance and does not believe that the adoption of this guidance will have a material effect on its consolidated financial statements.

In June 2014, the FASB issued ASU 2014-12—Compensation - Stock Compensation, which requires that a performance target that affects vesting and that could be achieved after the requisite service period be treated as a performance condition. ASU 2014-12 is effective for annual reporting periods, and interim periods within those years, beginning after December 15, 2015. Early adoption is permitted. The amendments may be applied prospectively to all awards granted or modified after the effective date or retrospectively to all awards with performance targets that are outstanding as of the beginning of the earliest annual period presented. The Company does not expect this guidance to have a material effect on its consolidated financial statements. The Company expects to adopt this guidance in 2016.

In May 2014, the FASB issued ASU 2014-09—Revenue from Contracts with Customers, which will replace most existing revenue recognition guidance under GAAP. The core principle of the guidance is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The standard provides a five-step analysis of transactions to determine when and how revenue is recognized. In July 2015, the FASB deferred the effective date to annual reporting periods, and interim periods within those years, beginning after December 15, 2017. Early adoption at the original effective date of December 15, 2016 is permitted. The amendments may be applied retrospectively or as a cumulative-effect adjustment as of the date of adoption. The Company has not yet selected a method of adoption and is currently evaluating the effect that the amendments will have on the consolidated financial statements.