Condensed Balance Sheets (unaudited) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 1,127,460	$ 978,957
Restricted cash	30,000	0
Short-term investment securities	106,298	105,321
Accounts receivable, net	56,043	73,807
Aircraft maintenance deposits, net	75,147	102,906
Income tax receivable	146,961	21,013
Prepaid expenses and other current assets	126,051	103,439
Total current assets	1,667,960	1,385,443
Property and equipment:
Flight equipment	4,071,980	3,730,751
Ground property and equipment	320,526	291,998
Less accumulated depreciation	(582,098)	(492,447)
Total property and equipment, net	3,810,408	3,530,302
Operating lease right-of-use assets	1,430,897	1,369,555
Pre-delivery deposits on flight equipment	382,652	291,930
Long-term aircraft maintenance deposits	63,623	67,682
Deferred heavy maintenance, net	376,745	361,603
Other long-term assets	35,659	36,897
Total assets	7,767,944	7,043,412
Current liabilities:
Accounts payable	41,060	43,601
Air traffic liability	452,023	315,408
Current maturities of long-term debt and finance leases	288,498	258,852
Current maturities of operating leases	128,536	120,662
Deferred salaries, wages and benefits	114,052	0
Other current liabilities	247,013	373,521
Total current liabilities	1,271,182	1,112,044
Long-term debt and finance leases, less current maturities	2,333,600	1,960,453
Operating leases, less current maturities	1,269,670	1,218,014
Deferred income taxes	517,537	469,292
Deferred gains and other long-term liabilities	32,793	22,277
Shareholders’ equity:
Common stock	27	7
Additional paid-in-capital	636,317	379,380
Treasury stock, at cost	(74,009)	(72,455)
Retained earnings	1,781,322	1,955,187
Accumulated other comprehensive income (loss)	(495)	(787)
Total shareholders’ equity	2,343,162	2,261,332
Total liabilities and shareholders’ equity	$ 7,767,944	$ 7,043,412