Represents cash dividends paid on share-based compensation

No definition available.

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- Definition

Related Party Transaction, Percentage Of Ownership Before Transaction

+ References

No definition available.

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- Definition

Stock Repurchase Program, Increase In Authorized Amount

+ References

No definition available.

+ Details

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- Definition

Amount of cash receipt from (payment to) bank; or stock received from (issuance to) bank in the settlement of the accelerated share repurchase agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 30
-Section 25
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6405686&loc=d3e22802-112653

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- Definition

Aggregate dividends declared during the period for each share of common stock outstanding.

+ References

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- Definition

Face amount or stated value per share of common stock.

+ References

+ Details

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- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21463-112644

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- Definition

Amount of paid and unpaid common stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK).

+ References

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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.

+ Details

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- Definition

Amount of paid and unpaid cash dividends declared and applicable to holders of share-based compensation, for example, but not limited to, non-vested shares, stock options, or restricted stock units.

+ References

No definition available.

+ Details

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- Definition

The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

+ References

+ Details

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- Definition

Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

+ References

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- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

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- Definition

Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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-Section 50
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Total cost of shares repurchased divided by the total number of shares repurchased.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

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- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

+ References

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- Definition

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21463-112644

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-Publisher FASB
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-Publisher FASB
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-Section S99
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-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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Shareholders' Equity and Dividends (Details) - USD ($)									1 Months Ended					3 Months Ended	12 Months Ended			36 Months Ended	48 Months Ended
Shareholders' Equity and Dividends (Details) - USD ($)	Feb. 28, 2018	Aug. 15, 2017	Oct. 03, 2016	Jan. 21, 2016	Aug. 13, 2015	Aug. 06, 2015	Mar. 17, 2014	Jan. 29, 2014	Mar. 31, 2017	Mar. 31, 2016	Nov. 30, 2015	Aug. 31, 2015	Mar. 31, 2015	Sep. 30, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2017	Dec. 31, 2017
Dividends Payable [Line Items]
Common stock, par value (usd per share)															$ 0.01	$ 0.01		$ 0.01	$ 0.01
Common stock, shares outstanding															52,461,996	52,971,232		52,461,996	52,461,996
Preferred stock, shares authorized (in shares)															50,000,000			50,000,000	50,000,000
Preferred stock, shares outstanding (in shares)															0	0		0	0
Increase in authorized amount		$ 100,000,000		$ 200,000,000		$ 125,000,000								$ 75,000,000
Stock repurchase program, authorized amount		$ 100,030,000.00		$ 325,000,000		$ 250,000,000
Treasury stock acquired (in shares)			2,050,000		2,667,378						1,038,280	3,705,658			961,000	13,144,000	3,706,000	17,811,000
Initial purchase price					$ 125,000,000
Aggregate purchase price					$ 100,000,000										$ 44,495,000	$ 359,885,000	$ 125,000,000	$ 529,380,000
Cost per share of stock acquired (usd per share)			$ 36.00		$ 37.49							$ 33.73			$ 46.32	$ 27.38	$ 33.73	$ 29.72
Stock repurchased during period, value			$ 73,800,000
Ownership percentage in Sotheby's outstanding Common Stock prior to sale			8.50%
Dividends declared (usd per share)				$ 0.10													$ 0.40
Cash dividend equivalents paid on share-based payments									$ 2,000,000	$ 1,400,000			$ 2,000,000				$ 279,000		$ 9,200,000
Subsequent Event
Dividends Payable [Line Items]
Increase in authorized amount	$ 100,000,000
Stock repurchase program, authorized amount	$ 195,700,000.0
Special Dividend
Dividends Payable [Line Items]
Dividends declared (usd per share)								$ 4.34
Dividends, common stock								$ 300,000,000
Share-based compensation based on special dividends							$ 10,000,000