Accumulated Other Comprehensive Loss (Amounts reclassified from accumulated other comprehensive loss) (Details) - USD ($) $ in Thousands		12 Months Ended
		Nov. 30, 2017	Nov. 30, 2016	Nov. 30, 2015
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amortization of net actuarial loss		$ 142	$ 79	$ 848
Amortization of prior service cost		1,556	1,556	1,556
Total reclassifications	[1]	1,698	$ 1,635	$ 2,404
Defined Benefit Plan, Expected Amortization of Prior Service Cost (Credit), Next Fiscal Year		100
Defined Benefit Plan, Expected Amortization of Gain (Loss), Next Fiscal Year		$ 1,600

[1] The accumulated other comprehensive loss components are included in the computation of net periodic benefit costs as further discussed in Note 20 – Postretirement Benefits.