Condensed Consolidated Statement of Cash Flows (USD $)
In Thousands, unless otherwise specified
3 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Statement of Cash Flows [Abstract]    
Cash flows from operating activities: $ 33,078 $ 4,330
Cash flows from investing activities:    
Acquisition of property and equipment and intangible assets (7,137) (27,111)
Pre-delivery payments for flight equipment (2,322) 0
Net cash used in investing activities (9,459) (27,111)
Cash flows from financing activities:    
Net proceeds of equity issuance 1 8
Net cash provided by (used in) financing activities 1 8
Net increase (decrease) in cash and cash equivalents 23,620 (22,773)
Cash and cash equivalents, beginning of period 394,643 155,659
Cash and cash equivalents, end of period 418,263 132,886
Supplemental disclosure:    
Interest 1,174 3,701
Income tax 251  
Non-cash transactions:    
Non-cash loan borrowings on pre-delivery payments for flight equipment $ 6,966 $ 0