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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Name:	us-gaap_StockRepurchasedDuringPeriodValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Shareholders' Equity (Details) - USD ($)		3 Months Ended
Shareholders' Equity (Details) - USD ($)	Feb. 01, 2021	Mar. 31, 2021	Mar. 31, 2020	Oct. 30, 2018
Distribution Made to Limited Partner [Line Items]
Repurchase aggregate cost		$ 193,900,000	$ 27,900,000
October 2018 Stock Repurchase Program
Distribution Made to Limited Partner [Line Items]
Authorized stock repurchase amount				$ 300,000,000.0
Remaining unused authorization for stock repurchase program		$ 147,100,000
Repurchase of common stock (in shares)		0	235,590
Repurchase aggregate cost			$ 27,900,000
Stock Repurchase Agreement with The Duchossois Group, Inc Affiliate
Distribution Made to Limited Partner [Line Items]
Repurchase of common stock (in shares)	1,000,000
Price per common stock (in dollars per share)	$ 193.94
Repurchase aggregate cost	$ 193,900,000