Minimum eligible age to participate in the plan

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Number of former employees hired.

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The number of new non-employee directors.

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Amount of decrease to equity for grantee's tax withholding obligation for award under share-based payment arrangement.

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The compensation expense recognized during the period pertaining to the deferred compensation arrangement.

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Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements payable within one year (or the operating cycle, if longer).

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Amount of contributions received by defined benefit plan from participant which increase benefit obligation.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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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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Number of shares authorized for issuance under share-based payment arrangement.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Net number of share options (or share units) granted during the period.

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Percentage of vesting of award under share-based payment arrangement.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of shares used to settle grantee's tax withholding obligation for award under share-based payment arrangement.

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Number, after forfeiture, of shares or units issued under share-based payment arrangement. Excludes shares or units issued under employee stock ownership plan (ESOP).

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Share-Based Compensation Plans - Additional Information (Details) shares in Thousands, $ in Thousands	1 Months Ended		12 Months Ended
	Aug. 31, 2019 director	Jun. 30, 2018 USD ($) employee shares	Dec. 31, 2020 USD ($) shares	Dec. 31, 2019 USD ($) shares	Dec. 31, 2018 USD ($) shares	Dec. 31, 2011
Share-based Compensation Plans
Shares available for grant			1,599
Minimum eligible age to participate in the plan			21 years
University made discretionary matching contributions \| $			$ 2,225	$ 2,529	$ 1,625
Maximum
Share-based Compensation Plans
Shares authorized			3,000
Restricted Stock
Share-based Compensation Plans
Shares granted			167	152	163
Unrecognized share-based compensation cost \| $			$ 25,332
Costs are expected to be recognized over a weighted average period			2 years 1 month 2 days
Forfeiture of shares by transferred employees at closing of transaction			15	16	95
Restricted Stock \| Grand Canyon University
Share-based Compensation Plans
Number of former employees hired \| employee		100
Shares issued under plan		82
Share-based compensation expense for restricted stock awards \| $		$ 7,880
Recognized deferred compensation plan expense for former GCE employees \| $		$ 9,568
Forfeiture of shares by transferred employees at closing of transaction		86
Restricted Stock \| Share-based Payment Arrangement, Employee
Share-based Compensation Plans
Shares granted			164	149	160
Vesting period			5 years
Shares withheld for taxes			62	68	151
Common stock in lieu of taxes \| $			$ 4,969	$ 8,127	$ 15,152
Restricted Stock \| Share-based Payment Arrangement, Nonemployee
Share-based Compensation Plans
Shares granted			3	3	3
Vesting period	1 year		1 year
Number of new non-employee directors \| director	2
Restricted Stock \| Share-based Compensation Award, Tranche One \| Share-based Payment Arrangement, Employee
Share-based Compensation Plans
Vesting right percentage			20.00%
Restricted Stock \| Share-based Compensation Award, Tranche Two \| Share-based Payment Arrangement, Employee
Share-based Compensation Plans
Vesting right percentage			20.00%
Restricted Stock \| Share-based Compensation Award, Tranche Three \| Share-based Payment Arrangement, Employee
Share-based Compensation Plans
Vesting right percentage			20.00%
Restricted Stock \| Share-based Compensation Award Tranche Four \| Share-based Payment Arrangement, Employee
Share-based Compensation Plans
Vesting right percentage			20.00%
Restricted Stock \| Share-based Compensation Award Tranche Five \| Share-based Payment Arrangement, Employee
Share-based Compensation Plans
Vesting right percentage			20.00%
Stock Options
Share-based Compensation Plans
Vesting period						5 years
Expiration period of options						10 years
Options granted			0	0	0