Capital Stock (Details) - USD ($)	3 Months Ended		6 Months Ended		138 Months Ended
	May 31, 2018	May 31, 2017	May 31, 2018	May 31, 2017	May 31, 2018
Equity, Class of Treasury Stock [Line Items]
Stock repurchased during the period			$ 6,419,000
Dividends per share (in dollars per share)	$ 0.47	$ 0.43	$ 0.47	$ 0.43
Total dividend approved			$ 20,738,000
Class A Common Stock | Stock Purchase Plan [Member]
Equity, Class of Treasury Stock [Line Items]
Authorized amount under Stock Purchase Plan	$ 530,000,000		$ 530,000,000		$ 530,000,000
Stock repurchased during the period (shares)			156,241		9,857,642
Average repurchase price (in dolllars per share)			$ 41.08
Stock repurchased during the period			$ 6,400,000		$ 364,800,000
Remaining repurchase authority under the Stock Purchase Plan	$ 165,200,000		$ 165,200,000		$ 165,200,000