Commitments and Contingencies (Details 1) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Summary of remaining aggregate lease commitments under operating leases having initial non-cancelable terms in excess of one year
2013	$ 43,078
2014	42,496
2015	41,768
2016	34,556
2017	24,240
Thereafter	32,176
Total	218,314
Aircraft [Member]
Summary of remaining aggregate lease commitments under operating leases having initial non-cancelable terms in excess of one year
2013	39,137
2014	39,137
2015	38,860
2016	31,964
2017	22,095
Thereafter	27,495
Total	198,688
Other [Member]
Summary of remaining aggregate lease commitments under operating leases having initial non-cancelable terms in excess of one year
2013	3,941
2014	3,359
2015	2,908
2016	2,592
2017	2,145
Thereafter	4,681
Total	$ 19,626