Amount of cash collateral released on repayment of debt.

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Percentage of equal instalments for repayment of principal amount of the term facility.

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Amount of amortization expense attributable to debt issuance costs.

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Amount of liabilities incurred by the acquirer as part of consideration transferred in a business combination.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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No definition available.

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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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No definition available.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount of increase (decrease) of the credit facility.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The cash outflow to repay long-term debt that is wholly or partially secured by collateral. Excludes repayments of tax exempt secured debt.

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Notes Payable and Other Noncurrent Liabilities (Details) - USD ($) $ in Thousands			3 Months Ended	6 Months Ended	12 Months Ended
	Oct. 31, 2019	Jan. 22, 2019	Mar. 31, 2019	Jun. 30, 2020	Dec. 31, 2019
Notes Payable and Other Noncurrent Liabilities
Repayments of term loan		$ 59,850
Cash collateral released on repayment of debt		61,667
Amended and restated credit agreement
Notes Payable and Other Noncurrent Liabilities
Amount of credit facilities		$ 325,000
Term of credit facility		5 years
Loan modification costs expensed			$ 150
Amended and restated credit agreement \| Orbis Education
Notes Payable and Other Noncurrent Liabilities
Acquisition consideration funded by credit agreement		$ 191,000
Amended and restated credit agreement \| 30-Day LIBOR
Notes Payable and Other Noncurrent Liabilities
Margin on variable interest rate		2.00%
Amended and restated credit agreement \| Term loan facility
Notes Payable and Other Noncurrent Liabilities
Amount of credit facilities		$ 243,750
Installment payment as a percentage of principal amount		5.00%
Loan modification costs		$ 1,639
Amended and restated credit agreement \| Term loan facility \| 30-Day LIBOR
Notes Payable and Other Noncurrent Liabilities
Margin on variable interest rate				2.17%	2.00%
Amended and restated credit agreement \| Revolving credit facility
Notes Payable and Other Noncurrent Liabilities
Amount of credit facilities		81,250
Loan modification costs		596
Amended and restated credit agreement \| Revolving credit facility \| Orbis Education
Notes Payable and Other Noncurrent Liabilities
Acquisition consideration funded by credit agreement		$ 6,250
Amended and restated credit agreement \| Revolving credit facility \| 30-Day LIBOR
Notes Payable and Other Noncurrent Liabilities
Margin on variable interest rate				2.17%	2.00%
Amendment - October 31, 2019 \| Term loan facility
Notes Payable and Other Noncurrent Liabilities
Amount of credit facilities	$ 150,625
Increase (decrease) in facility	(68,750)
Amendment - October 31, 2019 \| Revolving credit facility
Notes Payable and Other Noncurrent Liabilities
Amount of credit facilities	150,000
Increase (decrease) in facility	$ 68,750