Commitments And Contingencies Purchase Commitments and Minimum Licensing Fees (Details)	12 Months Ended
Dec. 31, 2020 USD ($)
Long-term Purchase Commitment [Line Items]
Purchase commitments	$ 201,000,000
Purchase Obligation, Fiscal Year Maturity [Abstract]
2021	80,000,000
2022	38,000,000
2023	34,000,000
2024	32,000,000
2025	22,000,000
Thereafter	229,000,000
Total purchase obligations	435,000,000
Sotheby’s International Realty®
Long-term Purchase Commitment [Line Items]
Licensing fees	2
Meredith Corporation \| Minimum
Long-term Purchase Commitment [Line Items]
Licensing fees	0.5
Meredith Corporation \| Maximum
Long-term Purchase Commitment [Line Items]
Licensing fees	$ 4

A sum paid to use a copyrighted item, such as a brand name, that is owned by someone else.

No definition available.

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- 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

Minimum amount to be expended to satisfy the terms of arrangements in which the entity has agreed to expend funds to procure goods or services, excluding long-term purchase commitments or unconditional purchase obligations.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(17))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

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-Name Accounting Standards Codification
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-SubTopic 210
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-Subparagraph (SX 210.7-03(a)(19))
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-Paragraph 1
-Subparagraph (SX 210.5-02(25))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Minimum amount of purchase arrangement in which the entity has agreed to expend funds to procure goods or services from a supplier.

+ References

No definition available.

+ Details

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- Definition

Amount of purchase arrangement to be paid after fifth fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

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- Definition

Amount of purchase arrangement to be paid in fifth fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

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- Definition

Amount of purchase arrangement to be paid in fourth fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of purchase arrangement to be paid in next fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of purchase arrangement to be paid in second fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

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- Definition

Amount of purchase arrangement to be paid in third fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- References

No definition available.

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