Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Current Assets
Cash and cash equivalents	$ 726,402	$ 103,029
Restricted cash	12,776	10,401
Short-term investments	0	879
Accounts receivable, net of allowance of $886 and $1,822, respectively	239,051	290,119
Prepaid expenses, assets held for sale and other current assets	177,978	228,103
Total current assets	1,156,207	632,531
Property and Equipment
Flight equipment	4,962,987	4,880,424
Ground equipment	86,341	83,584
Less: accumulated depreciation	(1,068,347)	(977,883)
Flight equipment modifications in progress	26,960	67,101
Property and equipment, net	4,007,941	4,053,226
Other Assets
Operating lease right-of-use assets	200,194	231,133
Deferred costs and other assets	378,567	391,895
Intangible assets, net and goodwill	73,841	76,856
Total Assets	5,816,750	5,385,641
Current Liabilities
Accounts payable	73,812	79,683
Accrued liabilities	653,253	481,725
Current portion of long-term debt and finance leases	275,017	395,781
Current portion of long-term operating leases	143,225	141,973
Total current liabilities	1,145,307	1,099,162
Other Liabilities
Long-term debt and finance leases	2,238,664	1,984,902
Long-term operating leases	322,450	392,832
Deferred taxes	111,802	74,040
Financial instruments and other liabilities	68,160	42,526
Total other liabilities	2,741,076	2,494,300
Commitments and contingencies	0	0
Stockholders’ Equity
Preferred stock, $1 par value; 10,000,000 shares authorized; no shares issued	0	0
Common stock, $0.01 par value; 100,000,000 shares authorized; 31,493,328 and 31,048,842 shares issued, 26,135,945 and 25,870,876 shares outstanding (net of treasury stock), as of June 30, 2020 and December 31, 2019, respectively	315	310
Additional paid-in-capital	801,002	761,715
Treasury stock, at cost; 5,357,383 and 5,177,966 shares, respectively	(217,711)	(213,871)
Accumulated other comprehensive loss	(2,347)	(2,818)
Retained earnings	1,349,108	1,246,843
Total stockholders’ equity	1,930,367	1,792,179
Total Liabilities and Equity	$ 5,816,750	$ 5,385,641