BASIS OF PRESENTATION (Policies)	9 Months Ended
Sep. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	The accompanying unaudited condensed consolidated financial statements of Knoll, Inc. (the “Company”) have been prepared with generally accepted accounting principles for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by generally accepted accounting principles for complete financial statements. In the opinion of management, all adjustments (consisting of normal recurring accruals) considered necessary for a fair presentation have been included. The condensed consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries and any partially owned subsidiaries that the Company has the ability to control. All significant intercompany balances and transactions have been eliminated in consolidation. Operating results for the three and nine month periods ended September 30, 2018 are not necessarily indicative of the results that may be expected for the year ended December 31, 2018. The condensed consolidated balance sheet of the Company, as of December 31, 2017, has been derived from the Company’s audited consolidated financial statements at that date but does not include all of the information and footnotes required by generally accepted accounting principles for complete financial statements. For further information, refer to the consolidated financial statements and footnotes thereto included in the Company’s annual report on Form 10-K for the year ended December 31, 2017.
New Accounting Pronouncements	New Accounting Pronouncements In May 2014, the FASB issued ASU No. 2014-09, “Revenue from Contracts with Customers”, which outlines a single comprehensive model for entities to use in accounting for revenue arising from contracts with customers. This ASU supersedes the revenue recognition requirements in FASB ASC Topic 605, “Revenue Recognition,” and most industry-specific guidance. The standard provides a five step model to be applied to all contracts with customers, with an underlying principle that an entity will recognize revenue to depict the transfer of goods or services to customers at an amount that the entity expects to be entitled to in exchange for those goods or services. The standard is effective for annual reporting periods beginning after December 15, 2017 and interim periods therein. The Company adopted the standard as of January 1, 2018. The Company has completed its assessment of the impact of the new standard and adopted the new standard for all open contracts as of January 1, 2018 using the modified retrospective transition method, and applied the guidance to report new disclosures surrounding the Company’s recognition of revenue. The adoption of the new standard did not have a material impact on the financial position of the Company, the results of its operations or its cash flows as of and for the three and nine months ended September 30, 2018, and the Company’s internal controls over financial reporting. There was no cumulative effect of adopting the standard at the date of initial application in retained earnings. The Company’s revenue recognition accounting policy has been updated for the new standard. Revenue is measured as the amount of consideration the Company expects to receive in exchange for transferring goods or providing services. The amount of consideration received and revenue recognized varies with changes in returns, rebates, cash sales incentives and other allowances offered to customers based on the Company’s experience. The new standard further requires quantitative and qualitative disclosures about the Company’s contracts with customers which have been included within this Form 10-Q. In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842), which supersedes the guidance in ASC 840, Leases. ASC 842 will be effective for the Company on January 1, 2019, and the Company will adopt the standard using the modified retrospective approach. While the Company continues to evaluate the provisions of ASC 842 to determine its impact, the primary effect of adopting the new standard will be to record assets and liabilities on the balance sheet for most leases including operating leases. Lessees will classify leases as either finance or operating leases and lessors classify all leases as sales-type, direct financing or operating leases. The statement of operations presentation and expense recognition for lessees for finance leases is similar to that of capital leases under Accounting Standards Codification (“ASC”) 840 with separate interest and amortization expense with higher periodic expense in the earlier periods of a lease. For operating leases, the statement of operations presentation and expense recognition is similar to that of operating leases under ASC 840 with single lease cost recognized on a straight-line basis. During the third quarter of 2018, the Company made progress on implementing the new standard which included surveying the Company’s businesses, assessing the Company’s portfolio of leases and compiling a central repository of active leases. The Company evaluated key policy elections and considerations under the standard which the Company will utilize to develop an internal policy to address the new standard requirements. Additionally, the Company selected a lease accounting software solution to support the new reporting requirements and started implementation of the software. While the Company continues to assess the impact on its accounting policies, internal control processes and related disclosures required under the new guidance, the Company expects to record a right-of-use asset and a lease liability for all leases with a term of greater than twelve months regardless of their classification. The Company does not believe the standard will materially affect its consolidated net earnings. These conclusions may change as the Company continues to evaluate the new standard or if there are any changes in the Company’s lease portfolio. In July 2018, the FASB issued clarifying guidance to the topic in ASUs No. 2018-11 and No. 2018-10, which defined several practical expedients for adoption and clarified new accounting methodologies. The Company is anticipating that it will elect the available practical expedients, including the transition option, upon adoption on January 1, 2019. In September 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments. ASU 2016-13 replaces the incurred loss impairment methodology for measuring and recognizing credit losses with a methodology that reflects expected credit losses and requires consideration of a broader range of reasonable and supportable information to inform credit loss estimates. This amendment is effective for fiscal years beginning after December 15, 2019 and will be effective for the Company on January 1, 2020. The Company does not believe there will be a material impact to the financial statements as a result of adopting this ASU. In March 2017, the FASB issued ASU 2017-07, Compensation-Retirement Benefits (Topic 715). The new standard requires the service cost component of net periodic benefit cost to be presented in the same income statement line as other employee compensation costs arising from services rendered during the period and the other components of net periodic benefit cost to be presented separately from the income statement lines that include service cost and outside of any subtotal of operating income. The Company adopted the new standard for the period beginning January 1, 2018, resulting in no change in presentation of the service cost component of net periodic benefit cost, which has historically been reported in selling, general and administrative expenses along with other employee compensation costs. The retrospective adoption resulted in a change in presentation of the other components of net periodic benefit cost for the year ended December 31, 2017, and interim periods therein, by reclassifying net periodic benefit income of $2.4 million and $7.2 million for the three and nine months ended September 30, 2017, respectively, from Selling, general and administrative expenses to Other income, net. In August 2017, the FASB issued ASU 2017-12, Derivatives and Hedging (Topic 815). The new standard is intended to better align a company’s risk management strategies and financial reporting for hedging relationships. Under the new guidance, more hedging strategies will be eligible for hedge accounting and the application of hedge accounting is simplified. In addition, the new guidance amends presentation and disclosure requirements. The guidance is effective for fiscal years beginning after December 15, 2018 with early adoption permitted, including the interim periods within those years. The Company early adopted the standard as of January 1, 2018. The adoption of the standard did not have a material impact on the Company’s consolidated financial statements. In February 2018, the FASB issued ASU 2018-02, Income Statement - Reporting Comprehensive Income (Topic 220). The new standard will allow a reclassification from accumulated other comprehensive income to retained earnings for stranded tax effects resulting from the Tax Cuts and Jobs Act (“Tax Act”). The amendments eliminate the stranded tax effects resulting from the Tax Act and will improve the usefulness of information reported to financial statements users. However, because the amendment only relates to the reclassification of the income tax effects of the Tax Act, the underlying guidance that requires that the effect of a change in tax laws or rates be included in income from continuing operations is not affected. The guidance is effective for fiscal years beginning after December 15, 2018 with early adoption permitted, including the interim periods within those years. The Company early adopted the standard effective January 1, 2018 and reclassified $6.3 million from accumulated other comprehensive income to retained earnings related to the Company’s pension liability. In March 2018, the FASB issued ASU 2018-05, Income Taxes (Topic 740) which incorporates the provision of SAB 118 into the accounting standards codification. The Security and Exchange Commission staff issued Staff Accounting Bulletin No. 118 (“SAB 118”) which provides guidance regarding situations when a registrant does not have the necessary information available, prepared, or analyzed (including computations) in reasonable detail to complete the accounting for certain income tax effects of the Tax Act. In accordance with SAB 118, the Company has made reasonable estimate of the effects on its existing deferred tax balances and one-time transition tax including impact of the assertion to repatriate foreign earnings. The ultimate impact of the Tax Act may differ from this estimate, possibly materially, due to change in interpretations and assumptions, and guidance that may be issued and actions the Company may take in response to the Tax Act. The estimated provision impact of the Tax Act, as disclosed in the Company’s annual report on Form 10-K, is anticipated to change as data becomes available through the tax return preparation process allowing more accurate scheduling of the deferred tax assets and liabilities primarily related to depreciable assets, inventory, employee compensation and commissions. The measurement period ends when a company has obtained, prepared and analyzed the information necessary to finalize its accounting, which is expected to be in the fourth quarter of 2018 in accordance with SAB 118 standards. In June 2018, the FASB issued ASU 2018-07, Compensation - Stock compensation (Topic 718) which simplifies several aspects of the accounting for nonemployee share-based payment transactions resulting from expanding the scope of Topic 718, Compensation-Stock Compensation, to include share-based payment transactions for acquiring goods and services from nonemployees. Some of the areas for simplification apply only to nonpublic entities. The amendments specify that Topic 718 applies to all share-based payment transactions in which a grantor acquires goods or services to be used or consumed in a grantor’s own operations by issuing share-based payment awards. The amendments also clarify that Topic 718 does not apply to share-based payments used to effectively provide (1) financing to the issuer or (2) awards granted in conjunction with selling goods or services to customers as part of a contract accounted for under Topic 606, Revenue from Contracts with Customers. The amendments in this Update are effective for public business entities for fiscal years beginning after December 15, 2018, including interim periods within that fiscal year. Early adoption is permitted. The Company does not plan to early adopt this ASU and the Company does not believe there will be a material impact to the financial statements as a result of adopting this ASU. In August 2018, the FASB issued ASU 2018-13, Fair Value Measurement (Topic 820) which modifies the disclosure requirements of fair value measurements in Topic 820, Fair Value Measurement. For public companies the ASU removes disclosure requirements for transfers between Level 1 and Level 2 of the fair value hierarchy, the policy for timing of transfers between levels and the valuation process for Level 3 fair value measurements. The ASU modifies the disclosure requirements for investments in certain entities that calculate net asset value and clarifies that the measurement uncertainty disclosure is to communicate information about the uncertainty in measurement as of the reporting date. The ASU adds the disclosure requirement for 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 fair value measurements. The amendments in this update are effective for all entities for fiscal years beginning after December 15, 2019 including interim periods within that fiscal year. Early adoption is permitted. The Company does not plan to early adopt this ASU and the Company does not believe there will be a material impact to the financial statements as a result of adopting this ASU. In August 2018, the FASB issued ASU 2018-14, Compensation - Retirement Benefits - Defined Benefit Plans - General (Subtopic 715-20). The ASU removes the requirements to disclose: amounts in accumulated other comprehensive income expected to be recognized as components of net periodic benefit cost over the next fiscal year, the amount and timing of plan assets expected to be returned to the employer, related party disclosures about the amount of future annual benefits covered by insurance and annuity contracts and significant transactions between the employer or related parties and the plan, and the effects of a one-percentage-point change in assumed health care cost trend rates. The ASU requires disclosure of the explanation of the reasons for significant gains and losses related to changes in the benefit obligation for the period. The amendments in the update are effective for all entities for fiscal years beginning after December 15, 2020 including interim periods within that fiscal year. Early adoption is permitted and the amendments in this update are required to be applied on a retrospective basis to all periods presented. The Company does not plan to early adopt this ASU and Company does not believe there will be a material impact to the financial statements as a result of adopting this ASU.
Revenue from Contract with Customer	Performance Obligations The Company recognizes revenue when performance obligations under the terms of a contract with its customer are satisfied. This occurs when the control of the goods and services have been transferred to the customer. Accordingly, revenue for sale of goods is generally recognized upon shipment or delivery depending on the shipping terms of the underlying contract. Revenue is measured as the amount of consideration the Company expects to receive in exchange for transferring goods or providing services. Amounts billed to customers for shipping and handling activities to fulfill the Company’s promise to transfer the goods are included in Sales, and costs incurred by the Company for the delivery of goods are classified as Cost of sales in the Condensed Consolidated Statements of Operations and Comprehensive Income. Sales tax, value added tax, and other taxes the Company collects concurrent with revenue-producing activities are excluded from revenue. The Company generally offers assurance-type warranties for its products. The specific terms and conditions of those warranties vary by the product. The Company estimates the costs that may be incurred under its warranties and records a liability in the amount of such costs at the time product revenue is recognized. Factors that affect the warranty liability include historical product-failure experience and estimated repair costs for identified matters. The Company periodically assesses the adequacy of its recorded warranty liabilities and adjusts the amounts as necessary. Practical Expedients Elected Incremental Costs of Obtaining a Contract - The Company has elected the practical expedient permitted in ASC 340-40-25-4, which permits an entity to recognize incremental costs to obtain a contract as an expense when incurred if the amortization period will be less than one year. Significant Financing Component - The Company has elected the practical expedient permitted in ASC 606-10-32-18, which allows an entity to not adjust the promised amount of consideration for the effects of a significant financing component if a contract has a duration of one year or less. As the Company’s contracts are typically less than one year in length, consideration will not be adjusted. The Company’s contracts include a standard payment term of 30 days, consequently there is no significant financing component within its contracts. Contract Balances The Company has contract assets consisting of Customer receivables in the Condensed Consolidated Balance Sheets which represent the amount of consideration the Company expects to be entitled to in exchange for the goods or services rendered to its customers. When the Company receives deposits, the recognition of revenue is deferred and results in the recognition of a contract liability (Customer deposits) presented as a component of Other Current Liabilities in the Condensed Consolidated Balance Sheets. Subsequent recognition of revenue and the satisfaction of the contract liability is typically less than one year as the Company’s standard contract is less than one year.

New Accounting Pronouncements

In May 2014, the FASB issued ASU No. 2014-09, “Revenue from Contracts with Customers”, which outlines a single comprehensive model for entities to use in accounting for revenue arising from contracts with customers. This ASU supersedes the revenue recognition requirements in FASB ASC Topic 605, “Revenue Recognition,” and most industry-specific guidance.

The standard provides a five step model to be applied to all contracts with customers, with an underlying principle that an entity will recognize revenue to depict the transfer of goods or services to customers at an amount that the entity expects to be entitled to in exchange for those goods or services. The standard is effective for annual reporting periods beginning after December 15, 2017 and interim periods therein. The Company adopted the standard as of January 1, 2018.

The Company has completed its assessment of the impact of the new standard and adopted the new standard for all open contracts as of January 1, 2018 using the modified retrospective transition method, and applied the guidance to report new disclosures surrounding the Company’s recognition of revenue. The adoption of the new standard did not have a material impact on the financial position of the Company, the results of its operations or its cash flows as of and for the three and nine months ended September 30, 2018, and the Company’s internal controls over financial reporting. There was no cumulative effect of adopting the standard at the date of initial application in retained earnings. The Company’s revenue recognition accounting policy has been updated for the new standard. Revenue is measured as the amount of consideration the Company expects to receive in exchange for transferring goods or providing services. The amount of consideration received and revenue recognized varies with changes in returns, rebates, cash sales incentives and other allowances offered to customers based on the Company’s experience. The new standard further requires quantitative and qualitative disclosures about the Company’s contracts with customers which have been included within this Form 10-Q.

In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842), which supersedes the guidance in ASC 840, Leases. ASC 842 will be effective for the Company on January 1, 2019, and the Company will adopt the standard using the modified retrospective approach. While the Company continues to evaluate the provisions of ASC 842 to determine its impact, the primary effect of adopting the new standard will be to record assets and liabilities on the balance sheet for most leases including operating leases. Lessees will classify leases as either finance or operating leases and lessors classify all leases as sales-type, direct financing or operating leases. The statement of operations presentation and expense recognition for lessees for finance leases is similar to that of capital leases under Accounting Standards Codification (“ASC”) 840 with separate interest and amortization expense with higher periodic expense in the earlier periods of a lease. For operating leases, the statement of operations presentation and expense recognition is similar to that of operating leases under ASC 840 with single lease cost recognized on a straight-line basis.

During the third quarter of 2018, the Company made progress on implementing the new standard which included surveying the Company’s businesses, assessing the Company’s portfolio of leases and compiling a central repository of active leases. The Company evaluated key policy elections and considerations under the standard which the Company will utilize to develop an internal policy to address the new standard requirements. Additionally, the Company selected a lease accounting software solution to support the new reporting requirements and started implementation of the software. While the Company continues to assess the impact on its accounting policies, internal control processes and related disclosures required under the new guidance, the Company expects to record a right-of-use asset and a lease liability for all leases with a term of greater than twelve months regardless of their classification. The Company does not believe the standard will materially affect its consolidated net earnings. These conclusions may change as the Company continues to evaluate the new standard or if there are any changes in the Company’s lease portfolio.

In July 2018, the FASB issued clarifying guidance to the topic in ASUs No. 2018-11 and No. 2018-10, which defined several practical expedients for adoption and clarified new accounting methodologies. The Company is anticipating that it will elect the available practical expedients, including the transition option, upon adoption on January 1, 2019.

In September 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments. ASU 2016-13 replaces the incurred loss impairment methodology for measuring and recognizing credit losses with a methodology that reflects expected credit losses and requires consideration of a broader range of reasonable and supportable information to inform credit loss estimates. This amendment is effective for fiscal years beginning after December 15, 2019 and will be effective for the Company on January 1, 2020. The Company does not believe there will be a material impact to the financial statements as a result of adopting this ASU.

In March 2017, the FASB issued ASU 2017-07, Compensation-Retirement Benefits (Topic 715). The new standard requires the service cost component of net periodic benefit cost to be presented in the same income statement line as other employee compensation costs arising from services rendered during the period and the other components of net periodic benefit cost to be presented separately from the income statement lines that include service cost and outside of any subtotal of operating income. The Company adopted the new standard for the period beginning January 1, 2018, resulting in no change in presentation of the service cost component of net periodic benefit cost, which has historically been reported in selling, general and administrative expenses along with other employee compensation costs. The retrospective adoption resulted in a change in presentation of the other components of net periodic benefit cost for the year ended December 31, 2017, and interim periods therein, by reclassifying net periodic benefit income of $2.4 million and $7.2 million for the three and nine months ended September 30, 2017, respectively, from Selling, general and administrative expenses to Other income, net.

In August 2017, the FASB issued ASU 2017-12, Derivatives and Hedging (Topic 815). The new standard is intended to better align a company’s risk management strategies and financial reporting for hedging relationships. Under the new guidance, more hedging strategies will be eligible for hedge accounting and the application of hedge accounting is simplified. In addition, the new guidance amends presentation and disclosure requirements. The guidance is effective for fiscal years beginning after December 15, 2018 with early adoption permitted, including the interim periods within those years. The Company early adopted the standard as of January 1, 2018. The adoption of the standard did not have a material impact on the Company’s consolidated financial statements.

In February 2018, the FASB issued ASU 2018-02, Income Statement - Reporting Comprehensive Income (Topic 220). The new standard will allow a reclassification from accumulated other comprehensive income to retained earnings for stranded tax effects resulting from the Tax Cuts and Jobs Act (“Tax Act”). The amendments eliminate the stranded tax effects resulting from the Tax Act and will improve the usefulness of information reported to financial statements users. However, because the amendment only relates to the reclassification of the income tax effects of the Tax Act, the underlying guidance that requires that the effect of a change in tax laws or rates be included in income from continuing operations is not affected. The guidance is effective for fiscal years beginning after December 15, 2018 with early adoption permitted, including the interim periods within those years. The Company early adopted the standard effective January 1, 2018 and reclassified $6.3 million from accumulated other comprehensive income to retained earnings related to the Company’s pension liability.

In March 2018, the FASB issued ASU 2018-05, Income Taxes (Topic 740) which incorporates the provision of SAB 118 into the accounting standards codification. The Security and Exchange Commission staff issued Staff Accounting Bulletin No. 118 (“SAB 118”) which provides guidance regarding situations when a registrant does not have the necessary information available, prepared, or analyzed (including computations) in reasonable detail to complete the accounting for certain income tax effects of the Tax Act. In accordance with SAB 118, the Company has made reasonable estimate of the effects on its existing deferred tax balances and one-time transition tax including impact of the assertion to repatriate foreign earnings. The ultimate impact of the Tax Act may differ from this estimate, possibly materially, due to change in interpretations and assumptions, and guidance that may be issued and actions the Company may take in response to the Tax Act. The estimated provision impact of the Tax Act, as disclosed in the Company’s annual report on Form 10-K, is anticipated to change as data becomes available through the tax return preparation process allowing more accurate scheduling of the deferred tax assets and liabilities primarily related to depreciable assets, inventory, employee compensation and commissions. The measurement period ends when a company has obtained, prepared and analyzed the information necessary to finalize its accounting, which is expected to be in the fourth quarter of 2018 in accordance with SAB 118 standards.

In June 2018, the FASB issued ASU 2018-07, Compensation - Stock compensation (Topic 718) which simplifies several aspects of the accounting for nonemployee share-based payment transactions resulting from expanding the scope of Topic 718, Compensation-Stock Compensation, to include share-based payment transactions for acquiring goods and services from nonemployees. Some of the areas for simplification apply only to nonpublic entities. The amendments specify that Topic 718 applies to all share-based payment transactions in which a grantor acquires goods or services to be used or consumed in a grantor’s own operations by issuing share-based payment awards. The amendments also clarify that Topic 718 does not apply to share-based payments used to effectively provide (1) financing to the issuer or (2) awards granted in conjunction with selling goods or services to customers as part of a contract accounted for under Topic 606, Revenue from Contracts with Customers. The amendments in this Update are effective for public business entities for fiscal years beginning after December 15, 2018, including interim periods within that fiscal year. Early adoption is permitted. The Company does not plan to early adopt this ASU and the Company does not believe there will be a material impact to the financial statements as a result of adopting this ASU.

In August 2018, the FASB issued ASU 2018-13, Fair Value Measurement (Topic 820) which modifies the disclosure requirements of fair value measurements in Topic 820, Fair Value Measurement. For public companies the ASU removes disclosure requirements for transfers between Level 1 and Level 2 of the fair value hierarchy, the policy for timing of transfers between levels and the valuation process for Level 3 fair value measurements. The ASU modifies the disclosure requirements for investments in certain entities that calculate net asset value and clarifies that the measurement uncertainty disclosure is to communicate information about the uncertainty in measurement as of the reporting date. The ASU adds the disclosure requirement for 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 fair value measurements. The amendments in this update are effective for all entities for fiscal years beginning after December 15, 2019 including interim periods within that fiscal year. Early adoption is permitted. The Company does not plan to early adopt this ASU and the Company does not believe there will be a material impact to the financial statements as a result of adopting this ASU.

In August 2018, the FASB issued ASU 2018-14, Compensation - Retirement Benefits - Defined Benefit Plans - General (Subtopic 715-20). The ASU removes the requirements to disclose: amounts in accumulated other comprehensive income expected to be recognized as components of net periodic benefit cost over the next fiscal year, the amount and timing of plan assets expected to be returned to the employer, related party disclosures about the amount of future annual benefits covered by insurance and annuity contracts and significant transactions between the employer or related parties and the plan, and the effects of a one-percentage-point change in assumed health care cost trend rates. The ASU requires disclosure of the explanation of the reasons for significant gains and losses related to changes in the benefit obligation for the period. The amendments in the update are effective for all entities for fiscal years beginning after December 15, 2020 including interim periods within that fiscal year. Early adoption is permitted and the amendments in this update are required to be applied on a retrospective basis to all periods presented. The Company does not plan to early adopt this ASU and Company does not believe there will be a material impact to the financial statements as a result of adopting this ASU.