Income Taxes (Details) - USD ($)	3 Months Ended
	Feb. 28, 2019	Feb. 28, 2018	Nov. 30, 2018
Income Tax Expense (Benefit), Continuing Operations [Abstract]
Income tax expense	$ 4,500,000	$ 117,300,000
Effective tax rate	13.00%	254.80%
Net (increase) reduction in valuation allowance	$ 3,300,000	$ (3,300,000)
Excess tax benefits related to stock-based compensation	(2,000,000)	(2,200,000)
Tax cuts and jobs act, non-cash charge		111,200,000
Tax cuts and jobs act, re-measurement of deferred tax assets		107,900,000
Tax credits	800,000	$ 4,000,000
Deferred tax assets	453,600,000		$ 465,400,000
Valuation allowance	20,300,000		23,600,000
Adjustments to deferred tax valuation allowance	0
Gross unrecognized taxe benefits (including interest and penalties)	$ 0		$ 0