Deferred Revenue Recognized of Refundable Prepaid Amounts

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- Definition

Minimum Term of Contract

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- Definition

Percentage of Refundable Amounts Included Within Contract Liabilities.

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- Definition

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

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- Definition

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

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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.

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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 current.

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- Definition

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- Definition

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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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.

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Revenue from Contracts with Customers (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Dec. 31, 2025
Disaggregation of Revenue [Line Items]
Percentage of Refundable Amounts Included Within Contract Liabilities	17.00%		17.00%		22.00%
Deferred Revenue Recognized in Period Related to Beginning Balance			$ 348.7
Deferred Revenue Recognized of Refundable Prepaid Amounts			$ 67.1
U.S. [Member]
Disaggregation of Revenue [Line Items]
Percentage of Revenue	83.00%	79.00%	81.00%	78.00%
Non-US [Member]
Disaggregation of Revenue [Line Items]
Percentage of Revenue	17.00%	21.00%	19.00%	22.00%
Transferred over Time [Member]
Disaggregation of Revenue [Line Items]
Percentage of Revenue	47.00%	51.00%	51.00%	53.00%
Transferred at Point in Time [Member]
Disaggregation of Revenue [Line Items]
Percentage of Revenue	53.00%	49.00%	49.00%	47.00%
Kaplan International [Member]
Disaggregation of Revenue [Line Items]
Contract Asset, Total	$ 29.0		$ 29.0		$ 36.5
Contract Asset, Current	5.8		5.8		4.4
Contract Asset, Noncurrent	23.2		23.2		32.1
Additional Contract Assets
Disaggregation of Revenue [Line Items]
Contract Asset, Current	$ 4.0		$ 4.0		$ 3.0
Long-term Contract with Customer [Member] \| Supplemental Education [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	57.00%		57.00%