| Summary of Significant Accounting Policies (Policies) | 12 Months Ended |
| Dec. 31, 2018 |
| Accounting Policies [Abstract] | |
| Basis of Presentation | —The Consolidated Financial Statements included herein have been prepared in accordance with accounting principles generally accepted in the United States of America ("U.S. GAAP") and pursuant to the rules and regulations of the Securities and Exchange Commission (the "SEC"). |
| Principles of Consolidation | Principles of Consolidation —The Consolidated Financial Statements include the accounts of our wholly-owned subsidiaries and Sotheby's (Beijing) Auction Co., Ltd. ("Sotheby's Beijing"), a joint venture in which we have a controlling 80% ownership interest. The net loss attributable to the minority owner of Sotheby's Beijing is reported as "Net Loss Attributable to Noncontrolling Interest" in our Consolidated Income Statements and the non-controlling 20% ownership interest is reported as "Noncontrolling Interest" within the Equity section of our Consolidated Balance Sheets. Intercompany transactions and balances among our subsidiaries are eliminated in consolidation. Equity investments through which we may significantly influence, but not control, the investee, are accounted for using the equity method. Under the equity method, our share of investee earnings or losses is recorded in our Consolidated Income Statements within Equity in Earnings of Investees. Our interest in the net assets of these investees is recorded on our Consolidated Balance Sheets within Other Long-Term Assets . |
| Foreign Currency Translation | Foreign Currency Translation —Assets and liabilities recorded in foreign currencies are translated at the exchange rate on the balance sheet date. Revenues, expenses, gains, and losses recorded in foreign currencies are translated using the monthly average exchange rates prevailing during the period in which they are recognized. Translation adjustments resulting from this process are recorded to Other Comprehensive (Loss) Income and reported on our Consolidated Balance Sheets within Accumulated Other Comprehensive Loss until the subsidiary is sold or liquidated, at which point the adjustments are recognized in Net Income. |
| Valuation of Inventory and Loan Collateral | Valuation of Inventory and Loan Collateral —The art market is not a highly liquid trading market. As a result, the valuation of art is inherently subjective and the realizable value of art often fluctuates over time. In estimating the realizable value of art held in inventory and art pledged as collateral for loans, we consider the following complex array of factors: (i) whether the property is expected to be offered at auction or sold privately, and the timing of any such sale; (ii) the supply and demand for the property, taking into account current art market conditions, as well as changing trends as to which collecting categories and artists are most sought after; (iii) recent sale prices achieved for comparable items within a particular collecting category and/or by a particular artist; (iv) the state of the global economy and financial markets; and (v) our intent and ability to hold the property in order to maximize its realizable value. Due to the inherent subjectivity involved in estimating the realizable value of art held in inventory and art pledged as collateral for loans, our estimates of realizable value may prove, with the benefit of hindsight, to be different than the amount ultimately realized upon sale. |
| Inventory | Inventory —Inventory consists of artworks that we own and includes the following general categories:(i) artworks that have been obtained as a result of the failure of guaranteed property to sell at auction; (ii) artworks that have been purchased opportunistically, including property acquired for sale at auction; and (iii) other objects obtained incidental to the auction process (e.g., as a result of buyer default). (See Note 21 for information related to auction guarantees.) Inventory is valued on a specific identification basis at the lower of cost or our estimate of realizable value (i.e., the expected sale price upon disposition). If there is evidence that the estimated realizable value of a specific item held in Inventory is less than its carrying value, a writedown is recorded to reflect our revised estimate of realizable va lue. For the years ended December 31, 2018 , 2017 , and 2016 , inventory writedowns totaled $9.5 million , $13.6 million , and $22.3 million , respectively, and are recorded within Cost of Inventory Sales in our Consolidated Income Statements. Although all of the items held in Inventory are available for immediate sale, the timing of eventual sale is difficult to predict due to the high value and unique nature of each item, as well as the cyclical nature of the global art market. We expect that the items held in Inventory will be sold in the ordinary course of our business during the normal operating cycle for such items. |
| Fixed Assets | Fixed Assets —Fixed Assets are stated at cost less accumulated depreciation and amortization. Depreciation is calculated using the straight-line method over the estimated useful life of the asset. Buildings are depreciated over a useful life of up to 50 years . Building improvements are depreciated over a useful life of up to 20 years . Furniture and fixtures are depreciated over a useful life of up to seven years. Leasehold improvements are amortized using the straight-line method over the lesser of the term of the related lease or the estimated useful life of the improvement. Computer software purchased or developed for internal use consists of the cost of purchased software, as well as direct external and internal software development costs. These costs are amortized on a straight-line basis over the estimated useful life of the software, which is typically between seven to ten years for enterprise systems and three years for other types of software. |
| Goodwill | Goodwill —Goodwill represents the excess of the purchase price paid over the fair value of net assets acquired in a business combination. Goodwill is not amortized, but is tested annually for impairment at the reporting unit level as of October 31 and between annual tests if indicators of potential impairment exist. These indicators could include a decline in our stock price and market capitalization, a significant change in the outlook for the reporting unit's business, lower than expected operating results, increased competition, legal factors, or the sale or disposition of a significant portion of a reporting unit. For reporting units with goodwill, an impairment loss is recognized for the amount by which the reporting unit's carrying value exceeds its fair value. The fair value of the reporting units in our Agency segment is determined in reference to a blend of the income and market approaches, and the fair value of our art advisory reporting unit is determined using a discounted cash flow methodology. (See Note 9 for information related to Goodwill.) The significant assumptions used in the income approach and discounted cash flow approach include (i) forecasted growth rates and (ii) forecasted profitability, both of which are estimated based on consideration of our historical performance and projections of our future performance, and (iii) discount rates that are used to calculate the value of future projected cash flows, which rates are derived based on our estimated weighted average cost of capital. The significant assumptions used in the market approach include selected multiples applied to certain operating metrics. Considerable judgment is necessary to evaluate the impact of operating changes and business initiatives in order to estimate future growth rates and profitability in order to estimate future cash flows and multiples. This is particularly true in a cyclical business, like that of Sotheby's. Future business results could significantly impact the evaluation of our goodwill which could have a material impact on the determination of whether a potential impairment exists and the size of any such impairment. |
| Intangible Assets | Intangible Assets —Intangible assets are amortized over their estimated useful lives unless the useful life of a particular intangible asset is deemed to be indefinite. If indicators of potential impairment exist, intangible assets with defined useful lives are tested for impairment based on our estimates of undiscounted cash flows and, if impaired, written down to fair value based on either discounted cash flows or appraised values. (See Note 9 for information related to Intangible Assets.) |
| Impairment of Long-Lived Assets | Impairment of Long-Lived Assets —Long-lived assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of the asset may not be recoverable. In such situations, long-lived assets are considered impaired when estimated future cash flows (undiscounted and without interest charges) resulting from the use of the asset and its eventual disposition are less than the asset's carrying amount. In such situations, the asset is written down to the present value of the estimated future cash flows. Factors that are considered when evaluating long-lived assets for impairment include a current expectation that it is more likely than not that the long-lived asset will be sold significantly before the end of its useful life, a significant decrease in the market price of the long-lived asset, and a significant change in the extent or manner in which the long-lived asset is being used. |
| Deferred Tax Assets & Liabilities | Deferred Tax Assets & Liabilities — We follow the liability method of accounting for income taxes under which deferred tax assets and liabilities are recognized, based on enacted tax rates, for the future tax consequences of (i) temporary differences between the tax basis of assets and liabilities and their reported amounts in our consolidated financial statements and (ii) operating loss and tax credit carry-forwards for tax purposes. A valuation allowance is recorded to reduce our deferred tax assets to the amount that is more likely than not to be realized. In assessing the need for the valuation allowance, management considers, among other things, projections of future taxable income and ongoing prudent and feasible tax planning strategies. If we determine that sufficient negative evidence exists (for example, if we experience cumulative three-year losses in a certain jurisdiction), then we will consider recording a valuation allowance against a portion or all of the deferred tax assets in that jurisdiction. If, after recording a valuation allowance, our projections of future taxable income and other positive evidence considered in evaluating the need for a valuation allowance prove, with the benefit of hindsight, to be inaccurate, it could prove to be more difficult to support the realization of our deferred tax assets. As a result, an additional valuation allowance could be required, which would have an adverse impact on our effective income tax rate and results. Conversely, if, after recording a valuation allowance, we determine that sufficient positive evidence exists in the jurisdiction in which the valuation allowance was recorded (for example, if we are no longer in a three-year cumulative loss position in the jurisdiction, and we expect to have future taxable income in that jurisdiction based upon our forecasts and the expected timing of deferred tax asset reversals), we may reverse a portion or all of the valuation allowance in that jurisdiction. In such situations, the adjustment made to the deferred tax asset would have a favorable impact on our effective income tax rate and on our results in the period such determination was made. |
| Revenue Recognition | Revenue Recognition (Agency Commissions and Fees) —Through our Agency segment, we accept works of art on consignment and match sellers (also known as consignors) to buyers through the auction or private sale process. In both auction and private sale transactions, we act as exclusive agent for the seller. Prior to offering a work of art for sale, we perform due diligence activities to authenticate and determine the ownership history and condition of the consigned artwork. The revenue recognition policy for each of the principal components of Agency Commissions and Fees is described below. (See Note 4 for a table that summarizes our revenues by segment and type for the years ended December 31, 2018, 2017, and 2016.) (1) Auction Commissions —In our role as auctioneer, we accept works of art on consignment and match sellers to buyers through the auction process. In an auction transaction, we act as exclusive agent for the seller. The terms of our arrangement with the seller are stipulated in a consignment agreement, which, among other things, entitles us to collect and retain an auction commission as compensation for our service. Our auction commission includes a premium charged to the buyer and, to a lesser extent, a commission charged to the seller, both of which are calculated as a percentage of the hammer price of the property sold at auction. In certain situations, in order to secure a high-value consignment, we may not charge a seller's commission and/or may share a portion of our buyer's premium with the seller. In situations when we share a portion of our buyer's premium with the seller, our auction commission revenue is recorded net of the amount paid to the seller. Prior to the date of the auction, we perform a number of activities in connection with our obligations under an auction consignment agreement, which may include: (i) transporting the consigned artwork to the location of the auction sale; (ii) performing due diligence to authenticate and determine the ownership history and condition of the consigned artwork; (iii) preparing the consigned artwork for auction (e.g., framing and cleaning); (iv) preparing catalogue content related to the consigned artwork (e.g., photography and description of the artwork); (v) marketing the artwork through exhibitions and advertising campaigns; (vi) establishing presale estimates for the consigned artwork in response to an assessment of buyer demand and overall market conditions; and (vii) conducting pre-auction bidder registration and qualification. The services associated with these activities are necessary components of our auction service, which culminates in the creation of a public marketplace for the sale and purchase of art that, if successful, results in the matching of the seller to a buyer upon the fall of the auctioneer's hammer. Upon the fall of the auctioneer's hammer, the highest bidder becomes legally obligated to pay the aggregate purchase price (i.e., the hammer price plus buyer's premium) and the consignor is legally obligated to relinquish the property in exchange for the net sale proceeds (i.e., the hammer price less any seller's commission and expense recoveries). However, if the bidding for an individual artwork does not reach its reserve price (i.e., the confidential minimum hammer price at which the consignor has agreed to sell), the sale is not completed, and we are not entitled to collect a commission. Accordingly, the consignor receives the benefit of our auction service only when the sale is completed, upon the fall of the auctioneer's hammer, at which point in time we recognize our auction commission revenue. Under the standard terms and conditions of our auction sales, we are not obligated to pay the consignor for property that has not been paid for by the buyer. If a buyer defaults on payment, the sale is cancelled, and the property is returned to the consignor. We continually evaluate the collectability of amounts due from individual buyers and only recognize auction commission revenue when the collection of the amount due from the buyer is probable. If we determine that payment from the buyer is not probable, a cancelled sale is recorded in the period in which that determination is made and the associated Accounts Receivable balance, including our auction commission, is reversed. Our judgments regarding the collectability of Accounts Receivable are based on an assessment of the buyer's payment history, discussions with the buyer, and the value of any property held as security against the buyer's payment obligation. Our judgments with respect to the collectability of amounts due from buyers for auction purchases may prove, with the benefit of hindsight, to be incorrect. Historically, cancelled sales have not been material in relation to the aggregate hammer price of property sold at auction. For artworks purchased at auction, the buyer is provided a five-year guarantee of authenticity. Subject to certain limitations, this guarantee generally attests to the authorship of the artwork. In the event a valid claim is made by the buyer under the authenticity guarantee, the sale is rescinded and we are obligated to refund the aggregate purchase price to the buyer. In these circumstances, the consignor is obligated to return any net sale proceeds paid to them. Outside of a valid authenticity claim, the buyer has no right to rescind an auction sale. The authenticity guarantee provided to the auction buyer is a product warranty that is associated with the provision of our auction service; it may not be purchased separately and does not provide an additional service to the buyer. (2) Auction Guarantees —From time-to-time, in the ordinary course of business, we will provide a guarantee to the consignor that their consigned artwork will achieve a specified minimum sale price at auction. This type of arrangement is known as an auction guarantee. If the property offered under an auction guarantee sells above the minimum guaranteed price, we are generally entitled to a share of the overage. In the event that the property sells for less than the minimum guaranteed price, we must perform under the auction guarantee by funding the shortfall between the sale price at auction and the amount of the auction guarantee. If the property offered under the auction guarantee does not sell, we must pay the amount of the auction guarantee to the consignor and then take ownership of the unsold property and may recover the amount paid through its future sale. In certain limited situations, if the guaranteed property fails to sell at auction or if the purchaser defaults, the consignor has the right to cancel the auction guarantee and retain the property. In situations when an item of guaranteed property does not sell and we take ownership of the property, it is taken into Inventory and recorded on our Consolidated Balance Sheets at the lower of its cost (i.e., the amount paid under the auction guarantee) or our estimate of the property’s net realizable value (i.e., the expected sale price upon its eventual disposition). The market for fine art, decorative art, and jewelry is not a highly liquid trading market. As a result, the valuation of property acquired as a result of failed auction guarantees is inherently subjective and its realizable value often fluctuates over time. Accordingly, the proceeds ultimately realized on the sale of previously guaranteed property may equal, exceed, or be less than the estimated net realizable value recorded as Inventory on our Consolidated Balance Sheets. We may reduce our financial exposure under auction guarantees through contractual risk sharing arrangements. Such auction guarantee risk sharing arrangements include irrevocable bid arrangements and, from time-to-time, partner sharing arrangements. An irrevocable bid is an arrangement under which a counterparty irrevocably commits to bid a predetermined price on the guaranteed property. If the irrevocable bid is not the winning bid, the counterparty is generally entitled to receive, as their fee, a share of the buyer's premium earned on the sale and/or a share of any auction guarantee overage. Such fees paid to irrevocable bid counterparties are recorded within Agency Direct Costs in the period of the sale. If the irrevocable bid is the winning bid, the counterparty may sometimes receive a fee as compensation for providing the irrevocable bid. This fee is netted against the counterparty's obligation to pay the aggregate purchase price (i.e., the hammer price plus buyer's premium) and is recorded as a reduction to our auction commission revenue in the period of the sale. In a partner sharing arrangement, a counterparty commits to fund: (i) a share of the difference between the sale price at auction and the amount of the auction guarantee, if the property sells for less than the minimum guaranteed price, or (ii) a share of the minimum guaranteed price if the property does not sell, while taking ownership of a proportionate share of the unsold property. In exchange for accepting a share of the financial exposure under the auction guarantee, if the property sells, the counterparty in a partner sharing arrangement is generally entitled to receive, as their fee, a share of the buyer's premium earned on the sale and/or a share of any auction guarantee overage. Such fees paid to the counterparties in auction guarantee partner sharing arrangements are recorded within Agency Direct Costs in the period of the sale. Similar to a standard auction transaction, for property sold under an auction guarantee, the consignor receives the benefit of our auction service only when the sale is completed, upon the fall of the auctioneer's hammer, at which point in time we recognize our auction commission revenue and any auction guarantee overage or shortfall. In the event that the property offered under an auction guarantee sells for a hammer price that is less than the minimum guaranteed price, the amount of the shortfall is recorded net of any buyer’s premium commission earned on the sale. An auction guarantee shortfall may also be recognized prior to the date of the auction if we determine that it is probable that the expected selling price of the property, including buyer's premium, will not exceed the amount of the auction guarantee. The amount of any auction guarantee overage or shortfall is reported on a net basis within Agency Commissions and Fees. (3) Consignor Expense Recoveries —We incur various direct costs in the fulfillment of our auction service. These costs principally relate to the transport of consigned artworks to the location of the auction sale, various sale marketing activities including catalogue production and distribution, and the exhibition of consigned artworks. Auction consignment agreements sometimes permit us to recover all or a portion of these costs from the consignor through a deduction from their net sale proceeds if the item is sold at auction. Such recoveries are recognized as revenue in the period of the auction sale. (4) Buyer Shipping Fees —Auction buyers may be charged a fee for shipping services associated with their purchased property. Such fees are recognized as revenue in the period when the shipping service is provided. (5) Private Sale Commissions —Private sale commission revenues are earned through the direct brokering of purchases and sales of art. Private sales are generally initiated by a client wishing to sell their artwork with Sotheby's acting as their exclusive agent in the transaction. Such arrangements are evidenced by a legally binding consignment agreement between us and the seller, which outlines the terms of the arrangement, including the desired sale price and the amount or rate of commission that we may earn if a sale is completed, as well as, in certain instances, the period of time over which the artwork may be offered for private sale. The terms of the private sale consignment agreement create our sole performance obligation, which is to broker a legally binding sale of the consigned artwork to a qualified buyer as exclusive agent for the seller. In connection with our efforts to fulfill our performance obligation under a private sale consignment agreement, we perform a number of activities, which may include: (i) transporting the consigned artwork to the location of the sale; (ii) performing due diligence to authenticate and determine the ownership history and condition of the consigned artwork; (iii) preparing the consigned artwork for sale (e.g., framing and cleaning); (iv) providing advice as to an appropriate asking price for the consigned artwork in response to an assessment of buyer demand and overall market conditions; (v) marketing the artwork to a select group of potential buyers or through theme-based private sale exhibitions; and (vi) completing all relevant administrative tasks related to completion of the sale. In certain situations, when completing a private sale, we may execute a legally binding agreement with the buyer stipulating the terms pursuant to which the buyer will purchase the consigned artwork. In situations when a legally binding buyer agreement is not executed, only an invoice is issued to provide the buyer with the information necessary for finalizing the transaction (e.g., the amount owed and any associated taxes and royalties, the payment due date, payment instructions, etc.). The consignor receives the benefit of our private sale service only upon the completion of a legally binding sale. For private sales where we execute a buyer agreement, the consignor receives the benefit of our private sale service and revenue is recognized at the point in time when the agreement is signed by the buyer. At this point in time, the buyer becomes legally obligated to pay the purchase price and the consignor is legally obligated to relinquish the property in exchange for the net sale proceeds (i.e., the purchase price less our commission). In the absence of an executed buyer agreement, the consignor receives the benefit of our private sale service and revenue is recognized at the point in time when the full purchase price is paid by the buyer. At this point in time, we have performed all of our service obligations in the transaction and the consignor is legally obligated to relinquish the property in exchange for the net sale proceeds. If we are not successful in completing a sale according to the terms of the private sale consignment agreement, we are not entitled to collect a commission. For artworks purchased in a private sale transaction, the buyer is provided a guarantee of authenticity for a period of up to five years. Subject to certain limitations, this guarantee generally attests to the authorship of the artwork. In the event a valid claim is made by the buyer under the authenticity guarantee, the sale is rescinded and we are obligated to refund the purchase price to the buyer. In these circumstances, the consignor is obligated to return any net sale proceeds paid to them. Outside of a valid authenticity claim, the buyer has no right to rescind a completed private sale. The authenticity guarantee provided to the buyer is a product warranty that is associated with the provision of our private sale service; it may not be purchased separately and does not provide an additional service to the buyer. (6) Other Agency Commissions and Fees —From time-to-time, we earn commissions and fees connected with sales of art brokered by third parties. These commissions and fees are recognized at a point in time in the period when we receive confirmation from the third parties that the sale has been completed. Revenue Recognition (Inventory Sales) —From time-to-time, the Agency segment earns revenue from the sale of items held in Inventory. Such sales may be consummated through either a private sale transaction or through an auction sale. For artworks that are sold privately, an executed agreement with the buyer is used to document the terms and conditions of the transaction. For artworks that are sold at auction, the sale is completed pursuant to the conditions of sale published in the corresponding auction catalogue. Regardless of the method of sale, title and control of the artwork are transferred to the buyer only upon payment of the full purchase price. Accordingly, sales of inventory are recognized at a point in time in the period when title and control of the artwork is transferred to the buyer. Revenue Recognition (Finance Revenues) —Finance revenues consist principally of interest income earned on Notes Receivable. Such interest income is recognized when earned, based on the amount of the outstanding loan, the applicable interest rate on the loan, and the length of time the loan is outstanding during the period. (See Note 5 for information related to Notes Receivable.) Revenue Recognition (Advisory Revenues) —Advisory revenues consist of fees earned from providing art-related advice to certain clients. These arrangements may be evidenced by a legally binding written retainer agreement with the client, which outlines the nature of the services to be provided and the amount of fees to be earned. Advisory retainer agreements are typically one year in duration. Advisory services are also sometimes provided on the basis of a verbal agreement with the client. For advisory arrangements with written retainer agreements, revenues are recognized ratably over time, based on the contractual period and as services are provided to the client. In the absence of a written retainer agreement, revenue recognition is deferred until we have performed our substantive service obligations and the client has made payment for those services, thereby evidencing the terms of the arrangement. Revenue Recognition (License Fee Revenues) —Prior to 2004, we were engaged in the marketing and brokerage of luxury residential real estate sales through Sotheby's International Realty ("SIR"). In 2004, we sold SIR to a subsidiary of Realogy Corporation ("Realogy"), formerly Cendant Corporation. In conjunction with the sale, we entered into an agreement with Realogy to license the SIR trademark and certain related trademarks for an initial 50 -year term with a 50 -year renewal option (the "Realogy License Agreement"). The Realogy License Agreement is applicable worldwide.The Realogy License Agreement provides for an ongoing license fee during its term based on the volume of commerce transacted under the licensed trademarks. We also license the Sotheby's name for use in connection with the art auction business in Australia, and art education services in the U.S. and the U.K. The license fees earned from these arrangements are sales-based and are recognized in the periods in which the underlying sales occur. Sales, Use and Value-Added Taxes —Sales, use and value-added taxes assessed by governmental authorities that are both imposed on and concurrent with revenue-producing transactions between us and our clients are reported on a net basis within revenues. Resale Royalties —In certain foreign jurisdictions, various resale royalties and other fees are imposed on auctioneers upon the completion of an auction sale. These royalties and fees are reported on a gross basis within Agency Direct Costs. Contract Balances —Following the completion of an auction or private sale, we invoice the buyer for the aggregate purchase price of the property, which includes our buyer's premium or private sale commission, as well as any applicable taxes and royalties. The amount owed by the buyer is recorded within Accounts Receivable, and the amount of net sale proceeds due to the seller is recorded within Client Payables. Upon collection from the buyer, we are obligated to remit the net proceeds to the seller after deducting our commissions and related fees, as well as any applicable taxes and royalties, which are ultimately paid to the appropriate taxing authority or royalty association. Under our standard auction payment terms, the purchase price is due from the buyer no more than 30 days after the sale date, with the net proceeds due to the consignor 35 days after the sale date. For private sales, payment from the buyer is typically due on the sale date, with the net sale proceeds due to the consignor shortly thereafter. We also sometimes provide extended payment terms to an auction or private sale buyer. For auctions, the extent to which extended payment terms are provided can vary considerably from selling season to selling season. Extended payment terms typically extend the payment due date to a date that is no longer than one year from the sale date. In limited circumstances, the payment due date may be extended to a date that is beyond one year from the sale date. When providing extended payment terms, we attempt to match the timing of cash receipt from the buyer with the timing of our payment to the consignor, but are not always successful in doing so. All extended payment term arrangements are approved by management under our internal corporate governance policy. In the limited circumstances when the buyer's payment due date is extended to a date that is beyond one year from the sale date, if the seller does not provide matched payment terms (i.e., we pay the seller before receiving payment from the buyer), the receivable balance is reclassified from Accounts Receivable to Notes Receivable on our Consolidated Balance Sheets. (See Note 5 for information on Agency segment Notes Receivable.) When the buyer's due date is extended to a date that is one year or less from the sale date, as a practical expedient, we do not record a discount to our commission to account for the effects of the financing component. However, in the limited circumstances when the buyer's due date is extended to a date that is beyond one year from the sale date, we record a discount to our commission revenue to reflect the financing component, if material. We maintain an Allowance for Doubtful Accounts against our Accounts Receivable balances, which principally includes estimated losses associated with situations when we have paid the net sale proceeds to the seller and it is probable that payment will not be collected from the buyer. The Allowance for Doubtful Accounts also includes an estimate of probable losses inherent in the remainder of the Accounts Receivable balance. The amount of the required allowance is based on the facts available to management, including the value of any property held as collateral, and is reevaluated and adjusted as additional facts become known. Based on all available information, we believe that the Allowance for Doubtful Accounts is adequate as of December 31, 2018; however, actual losses may ultimately exceed the recorded allowance. As of December 31, 2018 and 2017, the Allowance for Doubtful Accounts was $9.1 million and $8.7 million , respectively. Agency Direct Costs —A large portion of Agency Direct Costs relate to sale marketing expenses such as catalogue production and distribution, advertising and promotion costs, and traveling exhibition costs. Such costs are deferred and recorded on our Consolidated Balance Sheets within Prepaid Expenses and Other Current Assets until the date of the sale when they are recognized in our Consolidated Income Statements. |
| Salaries and Related Costs | Salaries and Related Costs —Salaries and related costs are not allocated to our cost of revenue, marketing expense, and general and administrative expense line items, as many of our employees perform duties that could be categorized across more than one of these line items. |
| Share-Based Payments | Share-Based Payments —We grant share-based payment awards as compensation to certain employees. The amount of compensation expense recognized for share-based payments is based, in part, on our estimate of the number of units or shares ultimately expected to vest as a result of employee service. For share-based payment awards that vest annually over a multi-year period of service, compensation expense is amortized over the requisite service period according to a graded vesting schedule. For share-based payment awards that have a single vesting opportunity at the end of a service period, compensation expense is amortized on a straight-line basis over the requisite service period. (See Note 23 for additional information related to share-based payments.) A substantial portion of the share-based payment awards vest only if we achieve established profitability (for awards granted prior to 2016) or certain return on invested capital (or "ROIC") targets (for awards granted beginning in 2016). The amount of compensation expense recognized for such performance-based awards is dependent upon our quarterly assessment of the likelihood of achieving these future profitability or ROIC targets. If, as a result of our assessment, we project that a greater number of performance share units will vest than previously anticipated, a life-to-date adjustment to increase compensation expense is recorded in the period such determination is made. Conversely, if, as a result of our assessment, we project that a lower number of performance share units will vest than previously anticipated, a life-to-date adjustment to decrease compensation expense is recorded in the period such determination is made. Accordingly, if our projections of future performance against these targets prove, with the benefit of hindsight, to be inaccurate, the amount of life-to-date and future compensation expense related to share-based payments could significantly increase or decrease. In 2015, we granted a share-based payment award to Thomas S. Smith, Jr., our President and CEO, with a single vesting opportunity after a five -year service period contingent upon the achievement of pre-determined levels of appreciation related to our common stock. The compensation expense recognized for this share-based payment is based on our estimate of the grant date fair value of the award. In developing this estimate, we considered then-current market conditions, historical data, and any other relevant data. |
| Recently Issued Accounting Standards | Recently Issued Accounting Standards Accounting Standards Adopted in 2018 Revenue Recognition —In May 2014, the Financial Accounting Standards Board (the "FASB") issued an Accounting Standards Update ("ASU") which amended previous revenue recognition guidance and requires more detailed disclosures to enable users of financial statements to understand the nature, amount, timing, and uncertainty of revenue and cash flows arising from contracts with customers. This ASU is codified in U.S. GAAP under Accounting Standards Codification ("ASC") 606, Revenue from Contracts with Customers . We adopted ASC 606 on January 1, 2018 using the full retrospective method. The adoption of ASC 606 did not impact the timing of our revenue recognition, but it changed the presentation of certain revenues and expenses previously reported on a net basis in our Consolidated Income Statements. Specifically, the following items previously reported on a net basis within Agency Commissions and Fees are now reported on a gross basis within Agency Direct Costs: (i) fees owed to the counterparties in auction guarantee risk sharing arrangements and (ii) fees owed to third parties who introduce us to auction or private sale consignors. In addition, consignor expense recoveries and buyer shipping fees previously reported on a net basis within Agency Direct Costs are now reported on a gross basis within Agency Commission and Fees. The tables below under "Summary of Adjustments to Prior Period Presentation" show the impact of the retrospective adoption of ASC 606 on our Consolidated Income Statements for the years ended December 31, 2017 and 2016. Statement of Cash Flows —In August 2016, the FASB issued ASU 2016-15, Statement of Cash Flows , which updated the guidance on how certain cash receipts and cash payments should be presented and classified within the statement of cash flows. We retrospectively adopted ASU 2016-15 on January 1, 2018. The adoption of ASU 2016-15 changed how we classify cash proceeds received from our investment in company-owned life insurance ("COLI"), which is held in a rabbi trust and used to fund certain deferred compensation liabilities. Prior to the adoption of ASU 2016-15, COLI proceeds were classified as cash inflows from operating activities, but are now classified as cash inflows from investing activities. The adoption of ASU 2016-15 also required us to make certain accounting policy elections with respect to the statement of cash flows. First, ASU 2016-15 clarifies that COLI premiums paid may be classified as cash outflows from operating or investing activities, or a combination of both. In connection with the adoption of ASU 2016-15, we made an accounting policy election to classify COLI premiums paid as cash outflows from operating activities, consistent with our previous presentation of such payments. Second, ASU 2016-15 allows distributions received from equity method investees to be classified using either the cumulative earnings approach or the nature of distribution approach. In connection with the adoption of ASU 2016-15, we made an accounting policy election to classify distributions received from equity method investees using the cumulative earnings approach, consistent with our previous presentation of such distributions. The other aspects of ASU 2016-15 did not result in a change to our existing accounting policies for the preparation of the statement of cash flows. The tables below under "Summary of Adjustments to Prior Period Presentation" show the impact of our retrospective adoption of ASU 2016-15 on our Consolidated Statements of Cash Flows for the years ended December 31, 2017 and 2016. In November 2016, the FASB issued ASU 2016-18, Statement of Cash Flows, to add and clarify guidance on the classification and presentation of restricted cash and restricted cash equivalents in the statement of cash flows. In particular, ASU 2016-18 requires that restricted cash and restricted cash equivalents be included within cash and cash equivalents when reconciling the beginning-of-period and end-of-period totals disclosed in the statement of cash flows. Transfers between restricted and unrestricted cash accounts are not to be reported within the statement of cash flows. Only restricted cash receipts or payments directly with third parties are to be reported in the statement of cash flows as either an operating, investing, or financing activity, depending on the nature of the transaction. We retrospectively adopted ASU 2016-18 on January 1, 2018. The tables below under "Summary of Adjustments to Prior Period Presentation" show the impact of our retrospective adoption of ASU 2016-18 on our Consolidated Statements of Cash Flows for the years ended December 31, 2017 and 2016. (See Note 15 for information related to our restricted cash balances.) Presentation of Pension and Postretirement Costs —In March 2017, the FASB issued ASU 2017-07, Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost , which requires that the service cost component of net periodic pension cost be presented in the same statement of operations line item as other employee compensation costs, while the remaining components of net periodic pension cost be presented outside of operating income (loss). We retrospectively adopted ASU 2017-07 on January 1, 2018. The tables below under "Summary of Adjustments to Prior Period Presentation" show the impact of our retrospective adoption of ASU 2017-07 on our Consolidated Income Statements for the for the years ended December 31, 2017 and 2016. (See Note 10 for information related to our defined benefit pension plan in the U.K.) Accumulated Comprehensive Income —On February 14, 2018, the FASB issued ASU 2018-02 to address industry concerns related to the application of ASC 740, Income Taxes , to certain provisions of the U.S. Tax Cuts and Jobs Act (the "Act"). Specifically, some constituents in the banking and insurance industries had expressed concerns about the requirement in ASC 740 that the effect of a change in tax laws or rates on deferred tax assets and liabilities be included in income from continuing operations in the reporting period that contains the enactment date of the change. That guidance applies even in situations in which the tax effects were initially recognized directly in other comprehensive income at the previous rate, resulting in stranded amounts in accumulated other comprehensive income ("AOCI") related to the income tax rate differential. We adopted ASU 2018-02 in the fourth quarter of 2018 and elected not to reclassify the stranded income tax effects in AOCI related to the Act to retained earnings in the statement of stockholders’ equity. Instead, any stranded income tax effects recorded in AOCI shall be reclassified into earnings in the period in which the underlying item is settled. Defined Benefit Plans —On August 28, 2018, the FASB issued ASU 2018-14, Disclosure Framework - Changes to the Disclosure Requirements for Defined Benefit Plans , which modifies the disclosure requirements for defined benefit pension plans and other postretirement plans. In particular, this standard requires companies to provide the reasons for significant gains and losses in pension benefit obligations ("PBO's") and to explain any other significant changes in PBO's and plan assets not otherwise apparent. We adopted ASU 2018-14 in the fourth quarter of 2018 and provided the required disclosures in this report. (See Note 10.) Summary of Adjustments to Prior Period Presentation The following tables summarize the impact of the retrospective adoption of ASC 606 and ASU 2017-07 on our Consolidated Income Statements for the years ended December 31, 2017 and 2016 (in thousands of dollars): Year Ended December 31, 2017 As Previously Reported ASC 606 Adjustment ASU 2017-07 Adjustment As Adjusted Revenues: Agency commissions and fees $ 741,580 $ 67,991 $ — $ 809,571 Total revenues $ 989,389 $ 67,991 $ — $ 1,057,380 Expenses: Agency direct costs $ 82,142 $ 67,991 $ — $ 150,133 Salaries and related $ 313,895 $ — $ 4,660 $ 318,555 Total expenses $ 819,054 $ 67,991 $ 4,660 $ 891,705 Operating income $ 170,335 $ — $ (4,660 ) $ 165,675 Non-operating income $ 2,385 $ — $ 4,660 $ 7,045 Net income attributable to Sotheby's $ 118,796 $ — $ — $ 118,796 Year Ended December 31, 2016 As Previously Reported ASC 606 Adjustment ASU 2017-07 Adjustment As Adjusted Revenues: Agency commissions and fees $ 671,833 $ 52,565 $ — $ 724,398 Total revenues $ 805,377 $ 52,565 $ — $ 857,942 Expenses: Agency direct costs $ 73,324 $ 52,565 $ — $ 125,889 Salaries and related $ 307,659 $ — $ 7,981 $ 315,640 Total expenses $ 682,761 $ 52,565 $ 7,981 $ 743,307 Operating income $ 122,616 $ — $ (7,981 ) $ 114,635 Non-operating income $ 3,134 $ — $ 7,981 $ 11,115 Net income attributable to Sotheby's $ 74,112 $ — $ — $ 74,112 The following tables summarize the impact of the retrospective adoption of ASU 2016-15 and ASU 2016-18 on our Consolidated Statement of Cash Flows for the years ended December 31, 2017, and 2016 (in thousands of dollars): Year Ended December 31, 2017 As Previously Reported ASU 2016-15 Adjustments ASU 2016-18 Adjustments As Adjusted Operating Activities: Restricted cash related to interest on 2022 Senior Notes $ (4,375 ) $ — $ 4,375 $ — Changes in other operating assets and liabilities $ (5,489 ) $ (2,100 ) $ — $ (7,589 ) Net cash provided by operating activities $ 366,185 $ (2,100 ) $ 4,375 $ 368,460 Investing Activities: Proceeds from company-owned life insurance $ — $ 2,100 $ — $ 2,100 Increase in restricted cash $ (3,276 ) $ — $ 3,276 $ — Net cash provided by investing activities $ 60,260 $ 2,100 $ 3,276 $ 65,636 Financing Activities: Restricted cash related to York Property Mortgage $ 1,527 $ — $ (1,527 ) $ — Restricted cash related to 2022 Senior Notes, principal and premium $ (307,875 ) $ — $ 307,875 $ — Net cash used by financing activities $ (383,971 ) $ — $ 306,348 $ (77,623 ) Effect of exchange rate changes $ 5,927 $ — $ 5,325 $ 11,252 Increase in cash, cash equivalents, and restricted cash (a) $ 48,401 $ — $ 319,324 $ 367,725 Cash, cash equivalents, and restricted cash at beginning of period (a) $ 496,031 $ — 60,170 $ 556,201 Cash, cash equivalents, and restricted cash at end of period (a) $ 544,432 $ — $ 379,494 $ 923,926 Year Ended December 31, 2016 As Previously Reported ASU 2016-15 Adjustments ASU 2016-18 Adjustments As Adjusted Operating Activities: Changes in other operating assets and liabilities $ 10,055 $ (2,182 ) $ — $ 7,873 Net cash provided by operating activities $ 158,370 $ (2,182 ) $ — $ 156,188 Investing Activities: Proceeds from company-owned life insurance $ — $ 2,182 $ — $ 2,182 Increase in restricted cash $ (26,097 ) $ — $ 26,097 $ — Net cash used by investing activities $ (120,418 ) $ 2,182 $ 26,097 $ (92,139 ) Financing Activities: Restricted cash related to York Property Mortgage $ (4,635 ) $ — $ 4,635 $ — Net cash used by financing activities $ (356,275 ) $ — $ 4,635 $ (351,640 ) Effect of exchange rate changes $ (34,343 ) $ — $ (1,129 ) $ (35,472 ) Decrease in cash, cash equivalents, and restricted cash (a) $ (352,666 ) $ — $ 29,603 $ (323,063 ) Cash, cash equivalents, and restricted cash at beginning of period (a) $ 848,697 $ — 30,567 $ 879,264 Cash, cash equivalents, and restricted cash at end of period (a) $ 496,031 $ — $ 60,170 $ 556,201 (a) Restricted cash is included only in the adjusted balances, reflecting the retrospective adoption of ASU 2016-18. Accounting Standards Not Yet Adopted Leases —In February 2016, the FASB issued ASU 2016-02, Leases , which requires long-term lease arrangements to be recognized as assets and liabilities on the balance sheet of the lessee. Under ASU 2016-02, a right-of-use asset and lease obligation will be recorded for all long-term leases, whether operating or financing, while the statement of operations will reflect lease expense for operating leases and interest expense for financing leases. On July 30, 2018, the FASB issued ASU 2018-11, which makes targeted improvements to ASU 2016-02 (together, the "New Lease Standard"). We will adopt the New Lease Standard on January 1, 2019, using the modified retrospective method and will not restate comparative periods presented in the year of adoption. We will elect the package of practical expedients available under the transition provisions of the New Lease Standard, including (i) not reassessing whether expired or existing contracts contain leases, (ii) not reassessing previous lease classification, and (iii) not revaluing initial direct costs for existing leases. In addition, we will elect the practical expedient which allows the aggregation of non-lease components with the related lease components when evaluating accounting treatment. Upon the adoption of the New Lease Standard, we expect to record a right-of-use asset and a corresponding operating lease liability of approximately $ 70 million to $ 80 million. In addition, as of January 1, 2019, we have implemented internal controls over financial reporting relevant to the New Lease Standard. We do not expect the New Lease Standard to have a material impact on our results of operations, cash flows, or existing debt covenants. (See Note 22 for additional information regarding our existing portfolio of leases.) Credit Losses —In June 2016, the FASB issued ASU 2016-13, Measurement of Credit Losses on Financial Instruments , which amends previously issued guidance regarding the impairment of financial instruments by creating an impairment model that is based on expected losses rather than incurred losses. ASU 2016-13 is effective for us beginning on January 1, 2020. We are currently assessing the potential impact of adopting ASU 2016-13 on our financial statements. Consolidation —In October 2018, the FASB issued ASU 2018-17, Targeted Improvements to Related Party Guidance for VIE's , which, among other things, addresses fees paid to decision makers and related party service providers. ASU 2018-17 is effective for us beginning on January 1, 2020. We are currently assessing the potential impact of adopting ASU 2018-17 on our financial statements. |
| Segment Reporting | Our operations are organized under two segments—the Agency segment and the Finance segment, which does business as and is referred to in this report as Sotheby's Financial Services (or "SFS"). Through our Agency segment, we accept works of art on consignment and match sellers (also known as consignors) to buyers through the auction or private sale process. In both auction and private sale transactions, we act as exclusive agent for the seller. Prior to offering a work of art for sale, we perform due diligence activities to authenticate and determine the ownership history and condition of the consigned artwork. To a much lesser extent, Agency segment activities also include the sale of artworks that are principally acquired as a consequence of the auction process, and RM Sotheby's, an equity investee that operates as an auction house for investment-quality automobiles. The Agency segment is an aggregation of operating segments which include the auction, private sale, and other related activities that are conducted within various collecting categories, all of which have similar economic characteristics and are similar in their services, customers, and the manner in which their services are provided. SFS is an art financing company that operates as a niche lender with the ability to tailor attractive financing packages for clients who wish to obtain immediate access to liquidity from their art assets. SFS leverages the art expertise of the Agency segment, skill in international law and finance, and access to capital to provide art collectors and dealers with financing secured by their works of art, allowing them to unlock the value in their collections. Art Agency, Partners (“AAP”), through which we offer art advisory services, provides art collectors with strategic guidance on collection identity and development, acquisitions, short and long-term planning, and provides advice to artists and artists' estates. In addition, from time-to-time, AAP brokers private art sales for its advisory clients. Our advisory services are classified within All Other for segment reporting purposes, along with our retail wine business, brand licensing activities, and the results from other certain equity method investments (see Note 6). |
| Earnings Per Share | Basic earnings per share —Basic earnings per share attributable to Sotheby's common shareholders is computed under the two-class method using the weighted average number of common shares outstanding during the period. The two-class method requires that the amount of net income attributable to participating securities be deducted from consolidated net income in the computation of basic earnings per share. In periods with a net loss, the net loss attributable to participating securities is not deducted from consolidated net loss in the computation of basic loss per share as the impact would be anti-dilutive. Our participating securities include unvested restricted stock units and unvested restricted stock shares held by employees, both of which have non-forfeitable rights to dividends. See Note 23 for information on our share-based payment programs. Diluted earnings per share —Diluted earnings per share attributable to Sotheby's common shareholders is computed in a similar manner to basic earnings per share under the two-class method, using the weighted average number of common shares outstanding during the period and, if dilutive, the weighted average number of potential common shares outstanding during the period. Our potential common shares principally include unvested performance share units held by employees and deferred stock units held by members of our Board of Directors. See Note 23 for information on our share-based payment programs. |
