Amount of revenue recognized from provider relief fund

No definition available.

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- Definition

Amount received from the government as relief under the CARES Act

+ References

No definition available.

+ Details

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- Definition

Minimum Term of Contract

+ References

No definition available.

+ Details

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- Definition

Percentage of Revenue Recognized During Period from Contract with Customer, Excluding Assessed Tax

+ References

No definition available.

+ Details

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- Definition

Revenue Remaining Performance Obligation Percentage of Revenue Expected to be Recognized Over Next 12 Months

+ References

No definition available.

+ Details

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- Definition

Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as noncurrent.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=121556615&loc=SL49130533-203044

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130549-203045

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121556615&loc=SL49130531-203044

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- Definition

Amount of revenue recognized that was previously reported as deferred or unearned revenue.

+ References

No definition available.

+ Details

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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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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Revenue from Contracts with Customers (Narrative) (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended	12 Months Ended
	Apr. 30, 2020	Jun. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Deferred revenue recognized in period related to beginning balance			$ 309.8
Provider Relief Fund [Member] \| Graham Healthcare Group [Member] \| CARES Act relief from COVID-19 [Member]
Disaggregation of Revenue [Line Items]
Government Relief, CARES Act		$ 7.4
Amount of Revenue Recognized From Provider Relief Fund			$ 5.7
Medicare Accelerated Advanced Payment Program Relief Fund [Member] \| Graham Healthcare Group [Member] \| CARES Act relief from COVID-19 [Member]
Disaggregation of Revenue [Line Items]
Government Relief, CARES Act	$ 31.5
Transferred over Time [Member]
Disaggregation of Revenue [Line Items]
Percentage of Revenue			73.00%	73.00%	80.00%
Transferred at Point in Time [Member]
Disaggregation of Revenue [Line Items]
Percentage of Revenue			27.00%	27.00%	20.00%
U.S. [Member]
Disaggregation of Revenue [Line Items]
Percentage of Revenue			78.00%	76.00%	76.00%
Non U.S. [Member]
Disaggregation of Revenue [Line Items]
Percentage of Revenue			22.00%	24.00%	24.00%
Kaplan International [Member]
Disaggregation of Revenue [Line Items]
Contract with Customer, Asset, Net, Noncurrent			$ 8.7
Supplemental Education [Member] \| Long-term Contract with Customer [Member]
Disaggregation of Revenue [Line Items]
Minimum Term of Contract			12 months
Revenue Remaining Performance Obligation Percentage of Revenue Expected to be Recognized Over Next 12 Months			63.00%