CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income (loss)	$ (161,586)	$ 117,817	$ (24,154)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	284,969	264,507	259,642
Stock based compensation expense	7,568	5,368	5,318
Loss on sale of property and equipment			4,016
Gain from equity ownership in TRIP Airlines			(24,922)
Gain from early extinguishment of debt	(1,279)	(33,660)
Capitalized Brasilia EMB-120 engine overhauls			(18,812)
Special items	465,649		74,777
Net increase (decrease) in deferred income taxes	(83,441)	73,844	5,054
Changes in operating assets and liabilities:
Decrease (increase) in restricted cash	(27)	3,366	637
Decrease in receivables	15,260	21,076	25,540
Increase in income tax receivable	(4,118)	(92)	(1,939)
Increase in inventories	(1,986)	(2,860)	(890)
Decrease (increase) in other current assets and prepaid aircraft rents	37,569	(28,598)	(25,985)
Decrease in deferred aircraft credits	(8,108)	(8,635)	(7,672)
Increase (decrease) in accounts payable and accrued aircraft rents	(47,563)	9,690	5,852
Increase (decrease) in other current liabilities	3,758	(4,498)	13,668
NET CASH PROVIDED BY OPERATING ACTIVITIES	506,665	417,325	290,130
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of marketable securities	(2,511,388)	(1,170,439)	(326,964)
Sales of marketable securities	2,388,168	1,299,069	398,148
Proceeds from the sale of aircraft, property and equipment	3,008	10,308	9,473
Proceeds from installment payment from sale of equity shares in TRIP Airlines			17,237
Proceeds from settlement of residual value guarantee aircraft agreements	90,000
Acquisition of property and equipment:
Aircraft and rotable spare parts	(1,138,963)	(710,871)	(653,473)
Deposits on aircraft	(650)
Buildings and ground equipment	(14,350)	(10,405)	(21,966)
Return of deposits on aircraft		1,850
Decrease (increase) in other assets	7,097	10,772	(7,681)
NET CASH USED IN INVESTING ACTIVITIES	(1,177,078)	(569,716)	(585,226)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from issuance of long-term debt	926,069	591,881	460,600
Principal payments on long-term debt	(302,158)	(354,277)	(185,357)
Net proceeds from issuance of common stock	8,142	9,754	2,692
Purchase of treasury stock		(18,726)	(8,414)
Decrease (increase) in debt issuance cost	(8,653)	2,779	(4,591)
Payment of cash dividends	(9,256)	(8,260)	(8,195)
NET CASH PROVIDED BY FINANCING ACTIVITIES	614,144	223,151	256,735
Increase (Decrease) in cash and cash equivalents	(56,269)	70,760	(38,361)
Cash and cash equivalents at beginning of period	203,035	132,275	170,636
CASH AND CASH EQUIVALENTS AT END OF PERIOD	146,766	203,035	132,275
Non-cash investing activities:
Acquisition of rotable spare parts	5,688
Cash paid during the period for:
Interest, net of capitalized amounts	76,589	80,657	67,763
Income taxes	$ 1,212	$ 5,104	$ 2,066