Long Term Debt (Details) (USD $)	0 Months Ended	6 Months Ended			0 Months Ended			6 Months Ended				0 Months Ended	6 Months Ended		0 Months Ended			6 Months Ended		0 Months Ended	6 Months Ended		6 Months Ended			0 Months Ended		6 Months Ended		0 Months Ended
	Jul. 16, 2014	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013	Jul. 16, 2014 Subsequent Event [Member]	Sep. 18, 2013 W O L F A340 L L C [Member]	Sep. 17, 2012 Class2012 A Term Notes [Member] Willis Engine Securitization Trust I I [Member]	Jun. 30, 2014 Class2012 A Term Notes [Member] Willis Engine Securitization Trust I I [Member] engine	Dec. 31, 2013 Class2012 A Term Notes [Member] Willis Engine Securitization Trust I I [Member]	Jun. 30, 2014 Class2012 A Term Notes [Member] Willis Engine Securitization Trust I I [Member] Minimum [Member]	Sep. 17, 2012 W E S T Notes [Member]	Sep. 28, 2012 Secured Debt5.50 Percent Five Year [Member]	Jun. 30, 2014 Secured Debt5.50 Percent Five Year [Member] engine	Dec. 31, 2013 Secured Debt5.50 Percent Five Year [Member]	Sep. 30, 2011 Secured Debt3.94 Percent Three Year [Member]	Jun. 30, 2014 Secured Debt3.94 Percent Three Year [Member]	Dec. 31, 2013 Secured Debt3.94 Percent Three Year [Member]	Jun. 30, 2014 Term Notes [Member] W O L F A340 L L C [Member]	Sep. 18, 2013 Term Notes [Member] W O L F A340 L L C [Member] item	Jan. 10, 2014 Secured Debt2.25 Percent Four Year [Member]	Jun. 30, 2014 Secured Debt2.25 Percent Four Year [Member] engine	Dec. 31, 2013 Secured Debt2.25 Percent Four Year [Member]	Jun. 30, 2014 Notes Payable Other Payables [Member]	Jun. 30, 2014 Notes Payable Other Payables [Member] Minimum [Member]	Jun. 30, 2014 Notes Payable Other Payables [Member] Maximum [Member]	Jun. 05, 2014 Revolving Credit Facility [Member]	Jun. 05, 2014 Revolving Credit Facility [Member]	Jun. 30, 2014 Revolving Credit Facility [Member]	Dec. 31, 2013 Revolving Credit Facility [Member]	Sep. 17, 2012 Revolving Credit Facility [Member] Willis Engine Securitization Trust [Member] engine
Long Term Debt
Maturity term	10 years				10 years			10 years				5 years			3 years					4 years				3 months	8 years
Interest rate, minimum (as a percent)																							2.40%
Interest rate, maximum (as a percent)																							5.50%
Maximum borrowing capacity under credit facility																											$ 700,000,000
Remaining borrowing capacity available																												357,000,000	88,000,000
Debt issuance costs																											4,700,000
Maximum borrowing capacity under credit facility before amendment																											450,000,000
Variable rate of debt		one-month LIBOR																one-month LIBOR			one-month LIBOR							LIBOR
Basis spread on variable rate (as a percent)																		4.00%			2.25%							2.50%
Net proceeds received from notes issued and sold		10,000,000	69,000,000				384,900,000
Total notes payable		753,820,000		787,614,000				361,500,000	370,600,000		435,900,000		7,900,000	8,200,000		300,000	1,000,000	25,900,000			15,100,000	15,800,000
Number of engines pledged as collateral								71					1								3									22
Fixed amortization of notes payable								0
Number of business days to pay interest								5 days
Fixed rate (as a percent)	2.75%				2.75%			5.50%					5.50%			3.94%
Initial term for interest payment	5 years				5 years
Percentage of the funding for the purchase of a corporate aircraft	100.00%				100.00%
Period of time over which maintenance obligations are projected								6 months
Minimum amount of cash from maintenance reserve payments required to be held in restricted cash account										9,000,000
Face amount	13,400,000				13,400,000		390,000,000					8,700,000			4,000,000				36,000,000
One-month LIBOR rate (as a percent)		0.16%	0.19%
Acquisition of remaining outstanding shares of previously held equity method investment (as a percent)						50.00%
Controlling interest assumed (as a percent)						100.00%
Number of term notes held																			2
Extended maturity term																										5 years
Aggregate maturities
2014		13,862,000
2015		34,307,000
2016 (includes $349.0 million outstanding on revolving credit facility)		27,588,000
2017		37,657,000
2018		33,804,000
Thereafter		606,602,000
Notes payable		$ 753,820,000		$ 787,614,000				$ 361,500,000	$ 370,600,000		$ 435,900,000		$ 7,900,000	$ 8,200,000		$ 300,000	$ 1,000,000	$ 25,900,000			$ 15,100,000	$ 15,800,000