XML 13 R28.htm IDEA: XBRL DOCUMENT v3.20.1

Leases (Details) $ in Millions	3 Months Ended
	Mar. 31, 2020 USD ($) property	Mar. 31, 2019 USD ($)
Other Commitments [Line Items]
Number of Leased Properties Owned by Related Parties | property	2
Costs and Expenses, Related Party	$ 0.2	$ 0.3
Lessee, Operating Lease, Leases Not yet Commenced, Term of Contract	4 years 7 months 6 days
Operating Real Estate Leases
Other Commitments [Line Items]
Lessee, Operating Lease, Leases Not Yet Commenced, Value	$ 2.6

X

- Definition

Lessee, Operating Leases, Leases Not Yet Commenced Value

+ References

No definition available.

+ Details

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Namespace Prefix:	asgn_
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Balance Type:	credit
Period Type:	instant

X

- Definition

Number of Leased Properties Owned by Related Parties

+ References

No definition available.

+ Details

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X

- Definition

Costs of sales and operating expenses for the period incurred from transactions with related parties.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.2)
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

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Balance Type:	debit
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X

- Definition

Term of lessee's operating lease not yet commenced, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918673-209980

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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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