Summary of Significant Accounting Policies (Policies)	9 Months Ended
Sep. 30, 2020
Accounting Policies [Abstract]
Cash, Cash Equivalents and Restricted Cash	Cash, Cash Equivalents and Restricted CashCash and cash equivalents include cash on hand and cash invested in highly liquid short-term securities, which have remaining maturities at the date of purchase of less than 90 days.
Goodwill	During the first quarter of 2020, we concluded that we had a triggering event related to our Fine Arts reporting unit, requiring us to perform an interim goodwill impairment test. The primary factor contributing to our conclusion was the expected impact of the COVID-19 pandemic to this particular business and its customers and revenue sources, which caused us to believe it was more likely than not that the carrying value of our Fine Arts reporting unit exceeded its fair value. During the first quarter of 2020, we performed an interim goodwill impairment test for our Fine Arts reporting unit utilizing a discounted cash flow model, with updated assumptions on future revenues, operating expenditures and capital expenditures. We concluded that the fair value of our Fine Arts reporting unit was less than its carrying value, and, therefore, we recorded a $23,000 impairment charge on the goodwill associated with this reporting unit during the first quarter of 2020. Factors that may impact these assumptions include, but are not limited to: (i) our ability to maintain, or grow, storage rental and service revenues in line with current expectations and (ii) our ability to manage our fixed and variable costs in line with potential future revenue declines.
Revenues	Data Center Lessor ConsiderationsOur Global Data Center Business features storage rental provided to customers at contractually specified rates over a fixed contractual period, which are accounted for in accordance with ASU 2016-02.
Accounts Receivable	Accounts Receivable In June 2016, the Financial Accounting Standards Board ("FASB") issued ASU No. 2016-13, Financial Instruments-Credit Losses-Measurement of Credit Losses on Financial Instruments (“ASU 2016-13”). ASU 2016-13 changes how entities will measure credit losses on most financial assets. The standard eliminates the probable initial recognition of estimated losses and provides a forward-looking expected credit loss model for accounts receivable, loans and other financial instruments. On January 1, 2020 we adopted ASU 2016-13 on a modified retrospective basis for all financial assets measured at amortized cost. The adoption of ASU 2016-13 did not result in a material impact on our consolidated financial statements. We now calculate and monitor our allowance considering future potential economic and macroeconomic conditions and reasonable and supportable forecasts for expected future collectability of our outstanding receivables, in addition to considering our past loss experience, current and prior trends in our aged receivables and credit memo activity. Our considerations when calculating our allowance include, but are not limited to, the following: the location of our businesses, the composition of our customer base, our product and service lines, potential future economic unrest, and potential future macroeconomic factors, including natural disasters and any impacts associated with the COVID-19 pandemic. Continued adjustments will be made should there be any material change to reasonable and supportable forecasts that may impact our likelihood of collection, as it becomes evident. Our highly diverse global customer base, with no single customer accounting for more than 1% of revenue during the nine months ended September 30, 2020, limits our exposure to concentration of credit risk.
Leases	Leases We lease facilities for certain of our warehouses, data centers and office space. We also have land leases, including those on which certain of our facilities are located.
Income (Loss) Per Share-Basic and Diluted	Income (Loss) Per Share—Basic and Diluted
Income Taxes	We provide for income taxes during interim periods based on our estimate of the effective tax rate for the year.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In August 2018, the FASB issued ASU No. 2018-13, Fair Value Measurement (Topic 820): Disclosure Framework – Changes to the Disclosure Requirements for Fair Value Measurement (“ASU 2018-13”), which makes a number of changes meant to add, modify or remove certain disclosure requirements associated with the movement of our financial assets and liabilities among the three levels of the fair value hierarchy. We adopted ASU 2018-13 on January 1, 2020. ASU 2018-13 did not have a material impact on our consolidated financial statements. In June 2016, the FASB issued ASU 2016-13. We adopted ASU 2016-13 on January 1, 2020 on a modified retrospective basis. See Note 2.d. for information regarding the impact of the adoption of ASU 2016-13 on our consolidated financial statements.
Correction in Presentation	Change in PresentationWe have historically classified our Significant Acquisition Costs (as defined in Note 2.x. to Notes to Consolidated Financial Statements included in our Annual Report) as components of Selling, general and administrative expenses and Cost of sales. Beginning in the fourth quarter of 2019, we present Significant Acquisition Costs as its own line item within Operating Expenses in our Condensed Consolidated Statements of Operations. The prior periods have been conformed to this presentation.
Segment Information	Adjusted EBITDA for each segment is defined as income (loss) from continuing operations before interest expense, net, provision (benefit) for income taxes, depreciation and amortization, and also excludes certain items that we believe are not indicative of our core operating results, specifically: (1) (gain) loss on disposal/write-down of property, plant and equipment, net (including real estate); (2) intangible impairments; (3) other expense (income), net (which includes foreign currency transaction (gains) losses, net, and debt extinguishment expense); (4) Significant Acquisition Costs; (5) Restructuring Charges (as defined in Note 10); and (6) COVID-19 Costs (as defined below). Internally, we use Adjusted EBITDA as the basis for evaluating the performance of, and allocating resources to, our operating segments.
Commitments and Contingencies	We are involved in litigation from time to time in the ordinary course of business. A portion of the defense and/or settlement costs associated with such litigation is covered by various commercial liability insurance policies purchased by us and, in limited cases, indemnification from third parties. There have been no material updates to the matters disclosed in Note 10 to Notes to Consolidated Financial Statements included in our Annual Report, and we continue to

Summary of Significant Accounting Policies (Policies)

9 Months Ended

Sep. 30, 2020

Cash, Cash Equivalents and Restricted Cash

Cash, Cash Equivalents and Restricted CashCash and cash equivalents include cash on hand and cash invested in highly liquid short-term securities, which have remaining maturities at the date of purchase of less than 90 days.

Goodwill

During the first quarter of 2020, we concluded that we had a triggering event related to our Fine Arts reporting unit, requiring us to perform an interim goodwill impairment test. The primary factor contributing to our conclusion was the expected impact of the COVID-19 pandemic to this particular business and its customers and revenue sources, which caused us to believe it was more likely than not that the carrying value of our Fine Arts reporting unit exceeded its fair value. During the first quarter of 2020, we performed an interim goodwill impairment test for our Fine Arts reporting unit utilizing a discounted cash flow model, with updated assumptions on future revenues, operating expenditures and capital expenditures. We concluded that the fair value of our Fine Arts reporting unit was less than its carrying value, and, therefore, we recorded a $23,000 impairment charge on the goodwill associated with this reporting unit during the first quarter of 2020. Factors that may impact these assumptions include, but are not limited to: (i) our ability to maintain, or grow, storage rental and service revenues in line with current expectations and (ii) our ability to manage our fixed and variable costs in line with potential future revenue declines.

Revenues

Data Center Lessor ConsiderationsOur Global Data Center Business features storage rental provided to customers at contractually specified rates over a fixed contractual period, which are accounted for in accordance with ASU 2016-02.

Accounts Receivable

In June 2016, the Financial Accounting Standards Board ("FASB") issued ASU No. 2016-13, Financial Instruments-Credit Losses-Measurement of Credit Losses on Financial Instruments (“ASU 2016-13”). ASU 2016-13 changes how entities will measure credit losses on most financial assets. The standard eliminates the probable initial recognition of estimated losses and provides a forward-looking expected credit loss model for accounts receivable, loans and other financial instruments.

On January 1, 2020 we adopted ASU 2016-13 on a modified retrospective basis for all financial assets measured at amortized cost. The adoption of ASU 2016-13 did not result in a material impact on our consolidated financial statements. We now calculate and monitor our allowance considering future potential economic and macroeconomic conditions and reasonable and supportable forecasts for expected future collectability of our outstanding receivables, in addition to considering our past loss experience, current and prior trends in our aged receivables and credit memo activity. Our considerations when calculating our allowance include, but are not limited to, the following: the location of our businesses, the composition of our customer base, our product and service lines, potential future economic unrest, and potential future macroeconomic factors, including natural disasters and any impacts associated with the COVID-19 pandemic. Continued adjustments will be made should there be any material change to reasonable and supportable forecasts that may impact our likelihood of collection, as it becomes evident. Our highly diverse global customer base, with no single customer accounting for more than 1% of revenue during the nine months ended September 30, 2020, limits our exposure to concentration of credit risk.

Leases

Leases We lease facilities for certain of our warehouses, data centers and office space. We also have land leases, including those on which certain of our facilities are located.

Income (Loss) Per Share-Basic and Diluted

Income (Loss) Per Share—Basic and Diluted

Income Taxes

We provide for income taxes during interim periods based on our estimate of the effective tax rate for the year.

Recent Accounting Pronouncements

In August 2018, the FASB issued ASU No. 2018-13, Fair Value Measurement (Topic 820): Disclosure Framework – Changes to the Disclosure Requirements for Fair Value Measurement (“ASU 2018-13”), which makes a number of changes meant to add, modify or remove certain disclosure requirements associated with the movement of our financial assets and liabilities among the three levels of the fair value hierarchy. We adopted ASU 2018-13 on January 1, 2020. ASU 2018-13 did not have a material impact on our consolidated financial statements.

In June 2016, the FASB issued ASU 2016-13. We adopted ASU 2016-13 on January 1, 2020 on a modified retrospective basis. See Note 2.d. for information regarding the impact of the adoption of ASU 2016-13 on our consolidated financial statements.

Correction in Presentation

Change in PresentationWe have historically classified our Significant Acquisition Costs (as defined in Note 2.x. to Notes to Consolidated Financial Statements included in our Annual Report) as components of Selling, general and administrative expenses and Cost of sales. Beginning in the fourth quarter of 2019, we present Significant Acquisition Costs as its own line item within Operating Expenses in our Condensed Consolidated Statements of Operations. The prior periods have been conformed to this presentation.

Segment Information

Adjusted EBITDA for each segment is defined as income (loss) from continuing operations before interest expense, net, provision (benefit) for income taxes, depreciation and amortization, and also excludes certain items that we believe are not indicative of our core operating results, specifically: (1) (gain) loss on disposal/write-down of property, plant and equipment, net (including real estate); (2) intangible impairments; (3) other expense (income), net (which includes foreign currency transaction (gains) losses, net, and debt extinguishment expense); (4) Significant Acquisition Costs; (5) Restructuring Charges (as defined in Note 10); and (6) COVID-19 Costs (as defined below). Internally, we use Adjusted EBITDA as the basis for evaluating the performance of, and allocating resources to, our operating segments.

Commitments and Contingencies

We are involved in litigation from time to time in the ordinary course of business. A portion of the defense and/or settlement costs associated with such litigation is covered by various commercial liability insurance policies purchased by us and, in limited cases, indemnification from third parties. There have been no material updates to the matters disclosed in Note 10 to Notes to Consolidated Financial Statements included in our Annual Report, and we continue to