Fair Value Measurements, Derivative Instruments and Hedging Activities - Fuel Derivatives Outstanding (Detail) bbl in Thousands, $ in Millions	3 Months Ended		6 Months Ended
	May. 31, 2015 USD ($) bbl $ / bbl	May. 31, 2014 USD ($)	May. 31, 2015 USD ($) bbl $ / bbl	May. 31, 2014 USD ($)
Derivative [Line Items]
(Losses) gains on fuel derivatives, net | $	$ (13)	$ 11	$ (181)	$ (6)
Fuel Derivatives 2015 Maturity
Derivative [Line Items]
Barrels | bbl	5,202		5,202
Percent of Estimated Fuel Consumption	50.00%		50.00%
Fuel Derivatives 2015 Maturity November 2011 Transaction Date
Derivative [Line Items]
Barrels | bbl	1,080		1,080
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	1,080		1,080
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	618		618
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	522		522
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	942		942
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	960		960
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	46.00%		46.00%
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	43.00%		43.00%
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	30.00%		30.00%
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 | $	$ 34	10	$ (78)	(7)
Realized gain (loss), net on derivatives | $	(47)	1	(103)	1
(Losses) gains on fuel derivatives, net | $	$ (13)	$ 11	$ (181)	$ (6)