Notes payable on real estate.

No definition available.

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- Definition

Through June 8, 2015, carrying amount of collateralized debt obligations with maturities initially due after one year or beyond the operating cycle, if longer, excluding the current portion. Obligations include, but not limited to, mortgage loans, chattel loans, and other borrowings secured by assets. June 9, 2015 and after, carrying value as of the balance sheet date of uncollateralized debt obligation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

+ References

No definition available.

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- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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- Definition

Fair value at acquisition-date of the equity interest in the acquiree held by the acquirer, immediately before the acquisition date for businesses combined in stages.

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- Definition

Percentage of equity in the acquiree held by the acquirer immediately before the acquisition date in a business combination.

+ References

No definition available.

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In a business combination achieved in stages, this element represents the amount of gain recognized by the entity as a result of remeasuring to fair value the equity interest in the acquiree it held before the business combination.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

Face (par) amount of the original debt instrument that was repurchased.

+ References

No definition available.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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The total fair value for all investments, comprising or included in the major category, of those certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments) for which the entity has intentions to sell or liquidate, but the specific assets for sale or liquidation have not been identified (for example, the entity intends to sell $10,000,000 of its investments in private equity funds, but the individual investments to be sold have not been identified).

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of an intangible asset (excluding goodwill) to fair value.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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The charge against earnings resulting from the aggregate write down of tangible assets from their carrying value to their fair value.

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Fair Value Measurements - Narrative (Details) - USD ($)	3 Months Ended	12 Months Ended
Fair Value Measurements - Narrative (Details) - USD ($)	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 28, 2020	Aug. 13, 2015	Sep. 26, 2014
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments in unconsolidated subsidiaries, fair value		$ 66,300,000	$ 124,300,000
Asset impairments		88,676,000	89,787,000	$ 0
Goodwill impairment	$ 25,000,000.0	25,000,000	0
Gain associated with remeasuring of investment in a previously unconsolidated subsidiary to fair value as of date		0	0	$ 100,420,000
Remaining controlling interest acquired percentage				50.00%
Fair value of investment in unconsolidated subsidiary at acquisition date				$ 110,100,000
Notes payable on real estate		$ 79,600,000	13,100,000
4.875% Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate		4.875%
4.875% Senior Notes \| Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate		4.875%				4.875%
Senior notes		$ 594,500,000	$ 593,600,000
5.25% Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate			5.25%
5.25% Senior Notes \| Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate		5.25%					5.25%
Senior notes			$ 423,000,000.0
Aggregate debt redeemed		$ 425,000,000.0			$ 425,000,000.0
Estimated Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior term loans		772,200,000	745,500,000
Estimated Fair Value \| 4.875% Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior notes		702,500,000	670,700,000
Estimated Fair Value \| 5.25% Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior notes			478,300,000
Actual Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior term loans		785,700,000	744,600,000
Actual Carrying Value \| 4.875% Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior notes		594,500,000	593,600,000
Actual Carrying Value \| 5.25% Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior notes			423,000,000.0
Previously Unconsolidated Subsidiary
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Gain associated with remeasuring of investment in a previously unconsolidated subsidiary to fair value as of date				$ 100,400,000
Percentage of remeasuring investment in previously unconsolidated subsidiary				50.00%
Global Workplace Solutions
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Asset impairments		50,200,000
Goodwill impairment		0
Real Estate Investments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Goodwill impairment		25,000,000
Property and equipment		13,500,000
Intangible asset impairment		$ 6,000,000.0	$ 89,800,000