Relationship with Timken and Related Entities	12 Months Ended
Dec. 31, 2016
Related Party Transactions [Abstract]
Relationship with Timken and Related Entities	Relationship with Timken and Related Entities Prior to the spinoff on June 30, 2014, TimkenSteel was managed and operated in the normal course of business with other affiliates of Timken. Transactions between Timken and TimkenSteel, with the exception of sale and purchase transactions and reimbursements for payments made to third-party service providers by Timken on TimkenSteel’s behalf, are reflected in equity in the Consolidated Balance Sheets as net parent investment and in the Consolidated Statements of Cash Flows as a financing activity in net transfers (to)/from Timken and affiliates. Corporate Costs/Allocations For the periods prior to April 1, 2014, the Consolidated Financial Statements include corporate costs incurred by Timken for services that were provided to or on behalf of Timken’s steel business, now TimkenSteel, including but not limited to legal, treasury, corporate administration, technology and human resource services. These costs consist of allocated cost pools and direct costs. Corporate costs were directly charged to, or allocated to, TimkenSteel using methods management believes are consistent and reasonable. TimkenSteel direct costs were incurred directly by TimkenSteel based on negotiated usage rates and dedicated employee assignments. These corporate charges and allocations were deemed paid by TimkenSteel to Timken in the period in which the costs were recorded in the Consolidated Statements of Operations. Net charges from Timken for these services, reflected in selling, general and administrative expenses, were $7.4 million for the year ended December 31, 2014. Effective April 1, 2014, TimkenSteel performed these functions using internal resources or services provided by third parties, certain of which were provided by Timken and directly charged to TimkenSteel. Transactions with Other Timken Businesses TimkenSteel sold finished goods to Timken. During the years ended December 31, 2016, 2015 and 2014, respectively, revenues from related-party sales of products totaled $32.7 million or 3.8% of net sales, $46.5 million, or 4.2% of net sales and $84.6 million or 5.1%, respectively. Prior to the spinoff, TimkenSteel recorded related-party receivables from Timken as Accounts receivable due from related-party in its Consolidated Balance Sheets. Upon separation, outstanding amounts were reclassified to trade receivables. TimkenSteel did not purchase material from Timken during the year ending December 31, 2016. TimkenSteel purchased less than $1.0 million during the year ended December 31, 2015, and approximately $1.0 million during the year ended December 31, 2014. In addition, certain of TimkenSteel’s third-party service providers were paid by Timken on behalf of TimkenSteel. TimkenSteel would subsequently reimburse Timken in cash for such payments. Prior to the spinoff, TimkenSteel recorded related-party payables to Timken as Accounts payable due to related party in its Consolidated Balance Sheets. Upon separation, outstanding amounts were reclassified to trade payables. Material Agreements Between TimkenSteel and Timken On June 30, 2014, TimkenSteel entered into a separation and distribution agreement and several other agreements with Timken to affect the spinoff and to provide a framework for the relationship with Timken. These agreements govern the relationship between TimkenSteel and Timken subsequent to the completion of the spinoff and provide for the allocation between TimkenSteel and Timken of assets, liabilities and obligations attributable to periods prior to the spinoff. Because these agreements were entered into in the context of a related party transaction, the terms may not be comparable to terms that would be obtained in a transaction between unaffiliated parties. Separation and Distribution Agreement — The separation and distribution agreement contains the key provisions relating to the spinoff, including provisions relating to the principal intercompany transactions required to effect the spinoff, the conditions to the spinoff and provisions governing the relationships between TimkenSteel and Timken after the spinoff. Tax Sharing Agreement — The tax sharing agreement generally governs TimkenSteel’s and Timken’s respective rights, responsibilities and obligations after the spinoff with respect to taxes for any tax period ending on or before the distribution date, as well as tax periods beginning before and ending after the distribution date. Generally, TimkenSteel is liable for all pre-distribution U.S. federal income taxes, foreign income taxes and non-income taxes attributable to TimkenSteel’s business, and all other taxes attributable to TimkenSteel, paid after the distribution. In addition, the tax sharing agreement addresses the allocation of liability for taxes that are incurred as a result of restructuring activities undertaken to effectuate the distribution. The tax sharing agreement also provides that TimkenSteel is liable for taxes incurred by Timken that arise as a result of TimkenSteel’s taking or failing to take, as the case may be, certain actions that result in the distribution failing to meet the requirements of a tax-free distribution under Section 355 of the Internal Revenue Code of 1986, as amended. Employee Matters Agreement — TimkenSteel entered into an employee matters agreement with Timken, which generally provides that TimkenSteel and Timken each has responsibility for its own employees and compensation plans, subject to certain exceptions as described in the agreement. In general, prior to the spinoff, TimkenSteel employees participated in various retirement, health and welfare, and other employee benefit and compensation plans maintained by Timken. Following the spinoff (or earlier, in the case of the tax-qualified defined benefit plans and retiree medical plans), pursuant to the employee matters agreement, TimkenSteel employees and former employees generally participate in similar plans and arrangements established and maintained by TimkenSteel. The employee matters agreement provides for the bifurcation of equity awards as described in Note 10 - Stock-Based Compensation. Among other things, the employee matters agreement also provides for TimkenSteel’s assumption of certain employment-related contracts that its employees originally entered into with Timken, the allocation of certain employee liabilities and the cooperation between TimkenSteel and Timken in the sharing of employee information. Transition Services Agreement — The transition services agreement, which expired on July 1, 2016, governed the process under which TimkenSteel and Timken provide and/or make available various administrative services and assets to each other. Services provided by Timken to TimkenSteel included certain services related to finance, facilities, information technology and employee benefits under LTA.

Relationship with Timken and Related Entities

Prior to the spinoff on June 30, 2014, TimkenSteel was managed and operated in the normal course of business with other affiliates of Timken. Transactions between Timken and TimkenSteel, with the exception of sale and purchase transactions and reimbursements for payments made to third-party service providers by Timken on TimkenSteel’s behalf, are reflected in equity in the Consolidated Balance Sheets as net parent investment and in the Consolidated Statements of Cash Flows as a financing activity in net transfers (to)/from Timken and affiliates.

Corporate Costs/Allocations

For the periods prior to April 1, 2014, the Consolidated Financial Statements include corporate costs incurred by Timken for services that were provided to or on behalf of Timken’s steel business, now TimkenSteel, including but not limited to legal, treasury, corporate administration, technology and human resource services. These costs consist of allocated cost pools and direct costs. Corporate costs were directly charged to, or allocated to, TimkenSteel using methods management believes are consistent and reasonable. TimkenSteel direct costs were incurred directly by TimkenSteel based on negotiated usage rates and dedicated employee assignments. These corporate charges and allocations were deemed paid by TimkenSteel to Timken in the period in which the costs were recorded in the Consolidated Statements of Operations. Net charges from Timken for these services, reflected in selling, general and administrative expenses, were $7.4 million for the year ended December 31, 2014. Effective April 1, 2014, TimkenSteel performed these functions using internal resources or services provided by third parties, certain of which were provided by Timken and directly charged to TimkenSteel.

Transactions with Other Timken Businesses

TimkenSteel sold finished goods to Timken. During the years ended December 31, 2016, 2015 and 2014, respectively, revenues from related-party sales of products totaled $32.7 million or 3.8% of net sales, $46.5 million, or 4.2% of net sales and $84.6 million or 5.1%, respectively. Prior to the spinoff, TimkenSteel recorded related-party receivables from Timken as Accounts receivable due from related-party in its Consolidated Balance Sheets. Upon separation, outstanding amounts were reclassified to trade receivables.

TimkenSteel did not purchase material from Timken during the year ending December 31, 2016. TimkenSteel purchased less than $1.0 million during the year ended December 31, 2015, and approximately $1.0 million during the year ended December 31, 2014. In addition, certain of TimkenSteel’s third-party service providers were paid by Timken on behalf of TimkenSteel. TimkenSteel would subsequently reimburse Timken in cash for such payments. Prior to the spinoff, TimkenSteel recorded related-party payables to Timken as Accounts payable due to related party in its Consolidated Balance Sheets. Upon separation, outstanding amounts were reclassified to trade payables.

Material Agreements Between TimkenSteel and Timken

On June 30, 2014, TimkenSteel entered into a separation and distribution agreement and several other agreements with Timken to affect the spinoff and to provide a framework for the relationship with Timken. These agreements govern the relationship between TimkenSteel and Timken subsequent to the completion of the spinoff and provide for the allocation between TimkenSteel and Timken of assets, liabilities and obligations attributable to periods prior to the spinoff. Because these agreements were entered into in the context of a related party transaction, the terms may not be comparable to terms that would be obtained in a transaction between unaffiliated parties.

Separation and Distribution Agreement — The separation and distribution agreement contains the key provisions relating to the spinoff, including provisions relating to the principal intercompany transactions required to effect the spinoff, the conditions to the spinoff and provisions governing the relationships between TimkenSteel and Timken after the spinoff.

Tax Sharing Agreement — The tax sharing agreement generally governs TimkenSteel’s and Timken’s respective rights, responsibilities and obligations after the spinoff with respect to taxes for any tax period ending on or before the distribution date, as well as tax periods beginning before and ending after the distribution date. Generally, TimkenSteel is liable for all pre-distribution U.S. federal income taxes, foreign income taxes and non-income taxes attributable to TimkenSteel’s business, and all other taxes attributable to TimkenSteel, paid after the distribution. In addition, the tax sharing agreement addresses the allocation of liability for taxes that are incurred as a result of restructuring activities undertaken to effectuate the distribution. The tax sharing agreement also provides that TimkenSteel is liable for taxes incurred by Timken that arise as a result of TimkenSteel’s taking or failing to take, as the case may be, certain actions that result in the distribution failing to meet the requirements of a tax-free distribution under Section 355 of the Internal Revenue Code of 1986, as amended.

Employee Matters Agreement — TimkenSteel entered into an employee matters agreement with Timken, which generally provides that TimkenSteel and Timken each has responsibility for its own employees and compensation plans, subject to certain exceptions as described in the agreement. In general, prior to the spinoff, TimkenSteel employees participated in various retirement, health and welfare, and other employee benefit and compensation plans maintained by Timken. Following the spinoff (or earlier, in the case of the tax-qualified defined benefit plans and retiree medical plans), pursuant to the employee matters agreement, TimkenSteel employees and former employees generally participate in similar plans and arrangements established and maintained by TimkenSteel. The employee matters agreement provides for the bifurcation of equity awards as described in Note 10 - Stock-Based Compensation. Among other things, the employee matters agreement also provides for TimkenSteel’s assumption of certain employment-related contracts that its employees originally entered into with Timken, the allocation of certain employee liabilities and the cooperation between TimkenSteel and Timken in the sharing of employee information.

Transition Services Agreement — The transition services agreement, which expired on July 1, 2016, governed the process under which TimkenSteel and Timken provide and/or make available various administrative services and assets to each other. Services provided by Timken to TimkenSteel included certain services related to finance, facilities, information technology and employee benefits under LTA.