v3.7.0.1
Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2017
Mar. 31, 2016
Operating activities:    
Net loss $ (15,248) $ (8,932)
Adjustments to reconcile net loss to net cash provided by operating activities:    
Depreciation and amortization 16,845 16,973
Deferred income taxes (7,883) 955
Loss on disposal of assets   359
Equity in loss of unconsolidated affiliate 1,003  
Inventory valuation reserves (1,293) 2,435
Changes in operating assets and liabilities (1,677) (28,133)
Net cash used in operating activities (8,253) (16,343)
Investing activities:    
Purchase of property and equipment (4,789) (8,519)
Proceeds from asset dispositions   850
Purchase of short-term investments (54,867) (77,677)
Proceeds from sale of short-term investments 67,659 76,184
Payment of deposits on aircraft (66) (66)
Net cash provided by (used in) investing activities 7,937 (9,228)
Financing activities:    
Proceeds from line of credit 37,300 83,500
Payments on line of credit (35,800) (53,300)
Repurchase of common stock (100) (500)
Net cash provided by (used in) financing activities 1,400 29,700
Increase in cash 1,084 4,129
Cash, beginning of period 2,596 2,407
Cash, end of period 3,680 6,536
Interest 14,114 13,691
Income taxes 0 0
Noncash investing activities:    
Other current liabilities and accrued payables related to purchase of property and equipment $ 348 $ 29,302