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Debt (Schedule of Long-term Debt) (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Jan. 31, 2020	Sep. 30, 2019
Debt Instrument [Line Items]
Total debt	$ 885,470		$ 977,155
Less unamortized discount and lender fees	(9,436)		(12,138)
Total net debt	876,034		965,017
Current portion of debt	(14,339)		(13,418)
Total long‑term debt	861,695		951,599
First Lien Term Loan, due December 20, 2024
Debt Instrument [Line Items]
Total debt	819,276	$ 826,000	928,753
Revolving Credit Facility
Debt Instrument [Line Items]
Total debt	0		0
Notes Payable, due July 31, 2023
Debt Instrument [Line Items]
Total debt	611		807
Equipment Financings [Member] \| Loans Payable
Debt Instrument [Line Items]
Total debt	63,918		45,960
Facility Financing [Member] \| Mortgages [Member] \| MAGENTO [Member]
Debt Instrument [Line Items]
Total debt	$ 1,665		$ 1,635
Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	3.00%
Minimum [Member] \| Equipment Financings [Member] \| Loans Payable
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	3.59%
Maximum [Member] \| Equipment Financings [Member] \| Loans Payable
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	8.07%