Hedging Hedges settled early due to 2015 ABL Restructuring (Details) - Feb. 05, 2015 € in Millions, $ in Millions	EUR (€) Mg $ / Mg $ / €	USD ($) Mg $ / Mg $ / €
Derivative [Line Items]
Settled hedge contracts, notional amount | $		$ 1
Bunker fuel forward contracts
Derivative [Line Items]
Settled hedged metric tons, notional amount | Mg	17,460	17,460
Bunker fuel forward contracts, contract average rate | $ / Mg	562.92	562.92
Foreign Exchange Forward, Average Rate [Member]
Derivative [Line Items]
Derivative, Notional Amount | €	€ 18
Foreign Exchange Put Option [Member]
Derivative [Line Items]
Currency derivatives - Contract Average Rate/Price (in $ per EUR)	1.37	1.37
Average rate collar [Member]
Derivative [Line Items]
Derivative, Notional Amount | €	€ 2
Average rate collar [Member] | Foreign Exchange Put Option [Member]
Derivative [Line Items]
Currency derivatives - Contract Average Rate/Price (in $ per EUR)	1.35	1.35
Average rate collar [Member] | Euro call option
Derivative [Line Items]
Currency derivatives - Contract Average Rate/Price (in $ per EUR)	1.43	1.43