Derivative Financial Instruments Foreign Currency Exchange Rate Risk (Details) £ in Thousands, AUD in Millions			3 Months Ended
	Feb. 25, 2015 GBP (£)	Feb. 25, 2015 USD ($)	Mar. 31, 2016 USD ($)	Mar. 31, 2015 GBP (£)	Mar. 31, 2015 USD ($)	Mar. 31, 2016 GBP (£)	Mar. 31, 2016 USD ($)	Mar. 25, 2015 GBP (£)	Mar. 25, 2015 USD ($)	Mar. 23, 2015 GBP (£)	Feb. 25, 2015 AUD	Feb. 25, 2015 GBP (£)	Feb. 25, 2015 USD ($)
Derivative [Line Items]
Foreign subsidiaries third-party debt denominated in local currencies | $							$ 515,200,000
Cash received on settlement of forward currency forward purchase contracts										£ 391,800
Net expense realized or recognized on cross-currency swap agreement | $			$ 0		$ (18,686,000)
Intercompany loan, amount								£ 120,000	$ 181,000,000
Accrued Liabilities						£ 7,600	$ 11,000,000
Foreign Exchange Forward [Member]
Derivative [Line Items]
Gain/(loss) reclassified from accumulated other comprehensive income/(loss) into earnings due to ineffectiveness | $			$ 0		0
British Pound foreign currency forward purchase contract 1 [Member]
Derivative [Line Items]
Notional amount												£ 307,100	$ 475,000,000
British Pound foreign currency forward purchase contract 2 [Member]
Derivative [Line Items]
Notional amount											AUD 163.8	£ 84,700
British Pound Foreign Currency Forward Contract 1 [Member]
Derivative [Line Items]
Notional amount						£ 60,000
Effective Date			Mar. 25, 2015
Settlement Date			Mar. 31, 2020
Exchange Rate						1.50	1.50
British Pound Foreign Currency Forward Contract 2 [Member]
Derivative [Line Items]
Notional amount						£ 60,000
Effective Date			Mar. 25, 2015
Settlement Date			Mar. 31, 2020
Exchange Rate						1.51	1.51
British Pound Foreign Currency Forward Contract 3 [Member]
Derivative [Line Items]
Notional amount						£ 2,035
Effective Date			Jun. 30, 2015
Settlement Date			Mar. 31, 2020
Exchange Rate						1.57	1.57
British Pound Foreign Currency Forward Contract 4 [Member]
Derivative [Line Items]
Notional amount						£ 1,846
Effective Date			Sep. 30, 2015
Settlement Date			Mar. 31, 2020
Exchange Rate						1.51	1.51
British Pound Foreign Currency Forward Contract 5 [Member]
Derivative [Line Items]
Notional amount						£ 1,873
Effective Date			Dec. 31, 2015
Settlement Date			Mar. 31, 2020
Exchange Rate						1.48	1.48
British Pound Foreign Currency Forward Contract 6 [Member]
Derivative [Line Items]
Notional amount						£ 1,881
Effective Date			Mar. 31, 2016
Settlement Date			Mar. 31, 2020
Exchange Rate						1.45	1.45
Freightliner [Member]
Derivative [Line Items]
Cash purchase price				£ 492,083	$ 733,006,000
Freightliner [Member] | Scenario, Plan [Member]
Derivative [Line Items]
Cash consideration paid to acquire business	£ 490,000	$ 755,000,000