Fair Value Measurements, Derivative Instruments and Hedging Activities - Fuel Derivatives Outstanding (Detail) bbl in Thousands, $ in Millions	3 Months Ended		9 Months Ended
	Aug. 31, 2015 USD ($) bbl $ / bbl	Aug. 31, 2014 USD ($)	Aug. 31, 2015 USD ($) bbl $ / bbl	Aug. 31, 2014 USD ($)
Derivative [Line Items]
(Losses) gains on fuel derivatives, net | $	$ (197)	$ 15	$ (378)	$ 10
Fuel Derivatives 2015 Maturity
Derivative [Line Items]
Barrels | bbl	2,601		2,601
Percent of Estimated Fuel Consumption	50.00%		50.00%
Fuel Derivatives 2015 Maturity November 2011 Transaction Date
Derivative [Line Items]
Barrels | bbl	540		540
Weighted-Average Floor Price (in dollars per barrel)	80		80
Weighted-Average Ceiling Price (in dollars per barrel)	114		114
Fuel Derivatives 2015 Maturity February 2012 Transaction Date
Derivative [Line Items]
Barrels | bbl	540		540
Weighted-Average Floor Price (in dollars per barrel)	80		80
Weighted-Average Ceiling Price (in dollars per barrel)	125		125
Fuel Derivatives 2015 Maturity June 2012 Transaction Date
Derivative [Line Items]
Barrels | bbl	309		309
Weighted-Average Floor Price (in dollars per barrel)	74		74
Weighted-Average Ceiling Price (in dollars per barrel)	110		110
Fuel Derivatives 2015 Maturity April 2013 Transaction Date
Derivative [Line Items]
Barrels | bbl	261		261
Weighted-Average Floor Price (in dollars per barrel)	80		80
Weighted-Average Ceiling Price (in dollars per barrel)	111		111
Fuel Derivatives 2015 Maturity May 2013 Transaction Date
Derivative [Line Items]
Barrels | bbl	471		471
Weighted-Average Floor Price (in dollars per barrel)	80		80
Weighted-Average Ceiling Price (in dollars per barrel)	110		110
Fuel Derivatives 2015 Maturity October 2014 Transaction Date
Derivative [Line Items]
Barrels | bbl	480		480
Weighted-Average Floor Price (in dollars per barrel)	79		79
Weighted-Average Ceiling Price (in dollars per barrel)	110		110
Fuel Derivatives 2016 Maturity
Derivative [Line Items]
Barrels | bbl	8,724		8,724
Percent of Estimated Fuel Consumption	53.00%		53.00%
Fuel Derivatives 2016 Maturity June 2012 Transaction Date
Derivative [Line Items]
Barrels | bbl	3,564		3,564
Weighted-Average Floor Price (in dollars per barrel)	75		75
Weighted-Average Ceiling Price (in dollars per barrel)	108		108
Fuel Derivatives 2016 Maturity February 2013 Transaction Date
Derivative [Line Items]
Barrels | bbl	2,160		2,160
Weighted-Average Floor Price (in dollars per barrel)	80		80
Weighted-Average Ceiling Price (in dollars per barrel)	120		120
Fuel Derivatives 2016 Maturity April 2013 Transaction Date
Derivative [Line Items]
Barrels | bbl	3,000		3,000
Weighted-Average Floor Price (in dollars per barrel)	75		75
Weighted-Average Ceiling Price (in dollars per barrel)	115		115
Fuel Derivatives 2017 Maturity
Derivative [Line Items]
Barrels | bbl	8,124		8,124
Percent of Estimated Fuel Consumption	49.00%		49.00%
Fuel Derivatives 2017 Maturity February 2013 Transaction Date
Derivative [Line Items]
Barrels | bbl	3,276		3,276
Weighted-Average Floor Price (in dollars per barrel)	80		80
Weighted-Average Ceiling Price (in dollars per barrel)	115		115
Fuel Derivatives 2017 Maturity April 2013 Transaction Date
Derivative [Line Items]
Barrels | bbl	2,028		2,028
Weighted-Average Floor Price (in dollars per barrel)	75		75
Weighted-Average Ceiling Price (in dollars per barrel)	110		110
Fuel Derivatives 2017 Maturity January 2014 Transaction Date
Derivative [Line Items]
Barrels | bbl	1,800		1,800
Weighted-Average Floor Price (in dollars per barrel)	75		75
Weighted-Average Ceiling Price (in dollars per barrel)	114		114
Fuel Derivatives 2017 Maturity October 2014 Transaction Date
Derivative [Line Items]
Barrels | bbl	1,020		1,020
Weighted-Average Floor Price (in dollars per barrel)	80		80
Weighted-Average Ceiling Price (in dollars per barrel)	113		113
Fuel Derivatives 2018 Maturity
Derivative [Line Items]
Barrels | bbl	5,700		5,700
Percent of Estimated Fuel Consumption	34.00%		34.00%
Fuel Derivatives 2018 Maturity January 2014 Transaction Date
Derivative [Line Items]
Barrels | bbl	2,700		2,700
Weighted-Average Floor Price (in dollars per barrel)	75		75
Weighted-Average Ceiling Price (in dollars per barrel)	110		110
Fuel Derivatives 2018 Maturity October 2014 Transaction Date
Derivative [Line Items]
Barrels | bbl	3,000		3,000
Weighted-Average Floor Price (in dollars per barrel)	80		80
Weighted-Average Ceiling Price (in dollars per barrel)	114		114
Fuel
Derivative [Line Items]
Unrealized gain (loss), net on derivatives | $	$ (137)	15	$ (215)	8
Realized gain (loss), net on derivatives | $	$ (60)	$ 0	$ (163)	$ 2