Overview and Basis of Presentation	9 Months Ended
Sep. 30, 2018
Accounting Policies [Abstract]
Overview and Basis of Presentation	Note 1. Overview and Basis of Presentation Description of Business Donnelley Financial Solutions, Inc. (the “Company” or “Donnelley Financial”) is a financial communications services company that supports global capital markets compliance and transaction needs for its corporate clients and their advisors (such as law firms and investment bankers) and global investment markets compliance and analytics needs for mutual fund companies, variable annuity providers and broker/dealers. With proprietary technology such as data storage and workflow collaboration tools, deep subject matter expertise and a global footprint, Donnelley Financial produces, manages, stores, distributes and translates documents and electronic communications in order to deliver timely financial communications to investors and documents in a manner that complies with regulatory commissions. Donnelley Financial’s Registration Statement on Form 10, as amended, was declared effective by the U.S. Securities and Exchange Commission (the “SEC”) on September 20, 2016. On October 1, 2016, Donnelley Financial became an independent publicly traded company through the distribution by R.R. Donnelley & Sons Company (“RRD”) of approximately 26.2 million shares, or 80.75%, of Donnelley Financial common stock to RRD shareholders (the “Separation”). Holders of RRD common stock received one share of Donnelley Financial common stock for every eight shares of RRD common stock held on September 23, 2016. As part of the Separation, RRD retained approximately 6.2 million shares of Donnelley Financial common stock, or a 19.25% interest in Donnelley Financial. Donnelley Financial’s common stock began regular-way trading under the ticker symbol “DFIN” on the New York Stock Exchange on October 3, 2016. On October 1, 2016, RRD also completed the previously announced separation of LSC Communications, Inc. (“LSC”), its publishing and retail-centric print services and office products business. On March 28, 2017, RRD completed the sale of 6.2 million shares of LSC common stock (RRD’s remaining ownership stake in LSC) in an underwritten public offering. Beginning in the quarter ended June 30, 2017, LSC no longer qualified as a related party, therefore amounts disclosed related to LSC are presented through March 31, 2017 only. On March 24, 2017, pursuant to the Stockholder and Registration Rights Agreement, dated as of September 30, 2016, by and between the Company and RRD, the Company filed a Registration Statement on Form S-1 to register the offering and sale of shares of the Company’s common stock retained by RRD. The Registration Statement on Form S-1, as amended, was declared effective by the SEC on June 13, 2017. On June 21, 2017, RRD completed the sale of approximately 6.1 million shares of the Company’s common stock in an underwritten public offering. Upon the consummation of the offering, RRD retained approximately 0.1 million shares of the Company’s common stock which were subsequently sold by RRD on August 4, 2017. In conjunction with the underwritten public offering, the underwriters exercised their option to purchase approximately 0.9 million of the Company’s shares (the “Option Shares”). The Company received approximately $18.8 million in net proceeds from the sale of the Option Shares, after deducting estimated underwriting discounts and commissions. The proceeds were used to reduce outstanding debt under the Revolving Facility (as defined in Note 15, Debt). Beginning in the quarter ended September 30, 2017, RRD no longer qualified as a related party, therefore amounts disclosed related to RRD are presented through June 30, 2017 only. Basis of Presentation The accompanying unaudited condensed consolidated financial statements include the accounts of Donnelley Financial and have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”) for interim financial information and in accordance with the rules and regulations of the SEC. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. The financial data presented herein should be read in conjunction with the audited consolidated and combined financial statements and accompanying notes included in the Company’s latest Annual Report on Form 10-K for the year ended December 31, 2017 filed with the SEC on February 28, 2018. In the opinion of management, the financial data presented includes all adjustments necessary to present fairly the financial position, results of operations and cash flows for the interim periods presented. Results of interim periods should not be considered indicative of the results for the full year. These unaudited condensed consolidated interim financial statements include estimates and assumptions of management that affect the amounts reported in the unaudited condensed consolidated financial statements. Actual results could differ from these estimates. Changes in Presentation Certain prior year amounts have been restated to conform to the Company’s current reporting unit structure. Due to the sale of the Language Solutions business, the Company made changes to the reporting units within the U.S. segment. The former Language Solutions and other reporting unit has been renamed “Language Solutions.” Certain results previously included within the former Language Solutions and other reporting unit are now included within the Investment Markets reporting unit.

Overview and Basis of Presentation

9 Months Ended

Sep. 30, 2018

Note 1. Overview and Basis of Presentation

Description of Business

Donnelley Financial Solutions, Inc. (the “Company” or “Donnelley Financial”) is a financial communications services company that supports global capital markets compliance and transaction needs for its corporate clients and their advisors (such as law firms and investment bankers) and global investment markets compliance and analytics needs for mutual fund companies, variable annuity providers and broker/dealers. With proprietary technology such as data storage and workflow collaboration tools, deep subject matter expertise and a global footprint, Donnelley Financial produces, manages, stores, distributes and translates documents and electronic communications in order to deliver timely financial communications to investors and documents in a manner that complies with regulatory commissions.

Donnelley Financial’s Registration Statement on Form 10, as amended, was declared effective by the U.S. Securities and Exchange Commission (the “SEC”) on September 20, 2016. On October 1, 2016, Donnelley Financial became an independent publicly traded company through the distribution by R.R. Donnelley & Sons Company (“RRD”) of approximately 26.2 million shares, or 80.75%, of Donnelley Financial common stock to RRD shareholders (the “Separation”). Holders of RRD common stock received one share of Donnelley Financial common stock for every eight shares of RRD common stock held on September 23, 2016. As part of the Separation, RRD retained approximately 6.2 million shares of Donnelley Financial common stock, or a 19.25% interest in Donnelley Financial. Donnelley Financial’s common stock began regular-way trading under the ticker symbol “DFIN” on the New York Stock Exchange on October 3, 2016. On October 1, 2016, RRD also completed the previously announced separation of LSC Communications, Inc. (“LSC”), its publishing and retail-centric print services and office products business. On March 28, 2017, RRD completed the sale of 6.2 million shares of LSC common stock (RRD’s remaining ownership stake in LSC) in an underwritten public offering. Beginning in the quarter ended June 30, 2017, LSC no longer qualified as a related party, therefore amounts disclosed related to LSC are presented through March 31, 2017 only.

On March 24, 2017, pursuant to the Stockholder and Registration Rights Agreement, dated as of September 30, 2016, by and between the Company and RRD, the Company filed a Registration Statement on Form S-1 to register the offering and sale of shares of the Company’s common stock retained by RRD. The Registration Statement on Form S-1, as amended, was declared effective by the SEC on June 13, 2017. On June 21, 2017, RRD completed the sale of approximately 6.1 million shares of the Company’s common stock in an underwritten public offering. Upon the consummation of the offering, RRD retained approximately 0.1 million shares of the Company’s common stock which were subsequently sold by RRD on August 4, 2017. In conjunction with the underwritten public offering, the underwriters exercised their option to purchase approximately 0.9 million of the Company’s shares (the “Option Shares”). The Company received approximately $18.8 million in net proceeds from the sale of the Option Shares, after deducting estimated underwriting discounts and commissions. The proceeds were used to reduce outstanding debt under the Revolving Facility (as defined in Note 15, Debt). Beginning in the quarter ended September 30, 2017, RRD no longer qualified as a related party, therefore amounts disclosed related to RRD are presented through June 30, 2017 only.

Basis of Presentation

The accompanying unaudited condensed consolidated financial statements include the accounts of Donnelley Financial and have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”) for interim financial information and in accordance with the rules and regulations of the SEC. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. The financial data presented herein should be read in conjunction with the audited consolidated and combined financial statements and accompanying notes included in the Company’s latest Annual Report on Form 10-K for the year ended December 31, 2017 filed with the SEC on February 28, 2018. In the opinion of management, the financial data presented includes all adjustments necessary to present fairly the financial position, results of operations and cash flows for the interim periods presented. Results of interim periods should not be considered indicative of the results for the full year. These unaudited condensed consolidated interim financial statements include estimates and assumptions of management that affect the amounts reported in the unaudited condensed consolidated financial statements. Actual results could differ from these estimates.

Changes in Presentation

Certain prior year amounts have been restated to conform to the Company’s current reporting unit structure. Due to the sale of the Language Solutions business, the Company made changes to the reporting units within the U.S. segment. The former Language Solutions and other reporting unit has been renamed “Language Solutions.” Certain results previously included within the former Language Solutions and other reporting unit are now included within the Investment Markets reporting unit.