Notes payable on real estate.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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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.

+ Details

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Balance Type:	credit
Period Type:	instant

- 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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Period Type:	duration

- Definition

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

+ References

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Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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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- Definition

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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- Definition

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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- Definition

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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- Definition

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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- Definition

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 ($)		3 Months Ended	12 Months Ended
Fair Value Measurements - Narrative (Details) - USD ($)	Jan. 01, 2021	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	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			$ 152,700,000	$ 66,300,000
Asset impairments			0	88,676,000	$ 89,787,000
Goodwill	$ 0	$ 25,000,000	0	25,000,000
Notes payable on real estate			$ 48,200,000	79,600,000
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%
Senior notes			$ 595,500,000	$ 594,500,000
2.500% Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate				2.50%	2.50%
2.500% Senior Notes \| Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate			2.50%
5.25% Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate			5.25%	5.25%	5.25%
5.25% Senior Notes \| Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate								5.25%
Aggregate debt redeemed				$ 425,000,000		$ 425,000,000
Estimated Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior term loans			$ 451,800,000	772,200,000
Estimated Fair Value \| 4.875% Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior notes			671,700,000	702,500,000
Estimated Fair Value \| 2.500% Senior Notes \| Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior notes			502,100,000
Actual Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior term loans			454,500,000	785,700,000
Actual Carrying Value \| 4.875% Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior notes			595,500,000	594,500,000
Actual Carrying Value \| 2.500% Senior Notes \| Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior notes			488,100,000
Global Workplace Solutions
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Asset impairments				50,200,000
Goodwill			0	0
Real Estate Investments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Goodwill			$ 0	25,000,000
Property and equipment				13,500,000
Intangible asset impairment				$ 6,000,000	$ 89,800,000