Summary of Significant Accounting Policies - Recent Accounting Standards or Updates Not Yet Effective (Details) - USD ($) $ in Millions	Dec. 31, 2019	Jan. 01, 2019
Lessee, Lease, Description [Line Items]
Recognition of additional lease assets	$ 199.8
Lease liabilities	$ 212.9
Accounting Standards Update 2016-02
Lessee, Lease, Description [Line Items]
Recognition of additional lease assets		$ 232.1
Lease liabilities		244.9
Decrease in deferred rent		$ 12.8

The cumulative difference between the rental payments required by a lease agreement and the rental income or expense recognized on a straight-line basis, or other systematic and rational basis more representative of the time pattern in which use or benefit is granted or derived from the leased property, expected to be recognized in income or expense over the term of the leased property by the lessor or lessee, respectively.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 25
-Paragraph 1
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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

Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
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- Definition

Amount of lessee's right to use underlying asset under operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-SubTopic 20
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