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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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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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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 cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Notes Payable and Other Noncurrent Liabilities (Details) - USD ($) $ in Thousands				1 Months Ended	3 Months Ended	9 Months Ended
	Nov. 01, 2019	Oct. 31, 2019	Jan. 22, 2019	Oct. 31, 2019	Mar. 31, 2019	Sep. 30, 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 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 interest rate						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 interest rate						2.00%
Subsequent Event \| Revolving credit facility
Notes Payable and Other Noncurrent Liabilities
Repayments of revolver				$ 26,250
Subsequent Event \| Amendment - October 31, 2019 \| Term loan facility
Notes Payable and Other Noncurrent Liabilities
Amount of credit facilities		$ 150,625		150,625
Increase (decrease) in facility		(68,750)
Subsequent Event \| Amendment - October 31, 2019 \| Revolving credit facility
Notes Payable and Other Noncurrent Liabilities
Amount of credit facilities		150,000		$ 150,000
Repayments of revolver	$ 68,750
Increase (decrease) in facility		$ 68,750