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Statements of Consolidated Cash Flows - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Operating Activities: |  |  |
Net income | $ 2,131 | $ 2,263 | $ 7,340
Adjustments to reconcile net income to net cash provided by operating activities - |  |  |
Deferred income taxes | 945 | 1,648 | (3,177)
Depreciation and amortization | 2,149 | 1,977 | 1,819
Special charges, non-cashportion | 35 | 391 | 247
Other operating activities | 142 | 109 | 115
Changes in operating assets and liabilities - |  |  |
Decrease in fuel hedge collateral |  | 26 | 551
Decrease in fuel derivatives |  | (20) | (305)
Decrease in other liabilities | (478) | (446) | (180)
Decrease in advanced purchase of miles | (865) | (249) | (224)
Increase (decrease) in frequent flyer deferred revenue | (142) | (60) | 6
Increase in other assets | (533) | (298) | (160)
Increase (decrease) in accounts payable | 66 | 239 | (77)
Increase (decrease) in advance ticket sales | 146 | (22) | 52
Increase in receivables | (183) | (16) | (15)
Net cash provided by operating activities | 3,413 | 5,542 | 5,992
Investing Activities: |  |  |
Capital expenditures | (3,998) | (3,223) | (2,747)
Purchases of short-term and other investments | (3,241) | (2,768) | (2,517)
Proceeds from sale of short-term and other investments | 3,177 | 2,712 | 2,707
Proceeds from sale of property and equipment | 12 | 28 | 86
Other, net | 120 | 13 | (136)
Net cash used in investing activities | (3,930) | (3,238) | (2,607)
Financing Activities: |  |  |
Proceeds from issuance of long-term debt and airport construction financing | 2,765 | 808 | 1,073
Repurchases of common stock | (1,844) | (2,614) | (1,233)
Payments of long-term debt | (901) | (1,215) | (2,178)
Principal payments under capital leases | (124) | (136) | (123)
Capitalized financing costs | (80) | (64) | (37)
Proceeds from the exercise of stock options | 2 | 6 | 16
Other, net | (13) | 2 | (13)
Net cash used in financing activities | (195) | (3,213) | (2,495)
Net increase (decrease) in cash, cash equivalents and restricted cash | (712) | (909) | 890
Cash, cash equivalents and restricted cash at beginning of year | 2,303 | 3,212 | 2,322
Cash, cash equivalents and restricted cash at end of year | 1,591 | 2,303 | 3,212
Investing and Financing Activities Not Affecting Cash: |  |  |
Property and equipment acquired through the issuance of debt and capital leases | 935 | 386 | 866
Equity interest in Republic Airways Holdings, Inc. received in consideration for bankruptcy claims | 92 |  |
Airport construction financing | 42 | 91 | 17
Operating lease conversions to capital lease |  | 12 | 285
Exchange of convertible notes for common stock |  |  | 202
Cash Paid During the Period for: |  |  |
Interest | 571 | 584 | 660
Income taxes | 20 | 14 | 15
United Airlines, Inc. |  |  |
Operating Activities: |  |  |
Net income | 2,149 | 2,264 | 7,301
Adjustments to reconcile net income to net cash provided by operating activities - |  |  |
Deferred income taxes | 929 | 1,650 | (3,136)
Depreciation and amortization | 2,149 | 1,977 | 1,819
Special charges, non-cashportion | 35 | 391 | 247
Other operating activities | 142 | 108 | 115
Changes in operating assets and liabilities - |  |  |
Decrease in fuel hedge collateral |  | 26 | 551
Decrease in fuel derivatives |  | (20) | (305)
Decrease in other liabilities | (479) | (444) | (181)
Decrease in advanced purchase of miles | (865) | (249) | (224)
Increase (decrease) in frequent flyer deferred revenue | (142) | (60) | 6
Increase in other assets | (533) | (251) | (160)
Increase (decrease) in accounts payable | 66 | 239 | (77)
Increase (decrease) in advance ticket sales | 146 | (22) | 52
Increase in receivables | (183) | (16) | (15)
Increase in intercompany receivables | (15) | (58) | (12)
Net cash provided by operating activities | 3,399 | 5,535 | 5,981
Investing Activities: |  |  |
Capital expenditures | (3,998) | (3,223) | (2,747)
Purchases of short-term and other investments | (3,241) | (2,768) | (2,517)
Proceeds from sale of short-term and other investments | 3,177 | 2,712 | 2,707
Proceeds from sale of property and equipment | 12 | 28 | 86
Other, net | 120 | 13 | (136)
Net cash used in investing activities | (3,930) | (3,238) | (2,607)
Financing Activities: |  |  |
Proceeds from issuance of long-term debt and airport construction financing | 2,765 | 808 | 1,073
Dividend to UAL | (1,844) | (2,614) | (1,233)
Payments of long-term debt | (901) | (1,215) | (2,178)
Principal payments under capital leases | (124) | (136) | (123)
Capitalized financing costs | (80) | (64) | (37)
Proceeds from the exercise of stock options | 2 | 6 | 16
Other, net | 1 | 9 | (2)
Net cash used in financing activities | (181) | (3,206) | (2,484)
Net increase (decrease) in cash, cash equivalents and restricted cash | (712) | (909) | 890
Cash, cash equivalents and restricted cash at beginning of year | 2,297 | 3,206 | 2,316
Cash, cash equivalents and restricted cash at end of year | 1,585 | 2,297 | 3,206
Investing and Financing Activities Not Affecting Cash: |  |  |
Property and equipment acquired through the issuance of debt and capital leases | 935 | 386 | 866
Equity interest in Republic Airways Holdings, Inc. received in consideration for bankruptcy claims | 92 |  |
Airport construction financing | 42 | 91 | 17
Operating lease conversions to capital lease |  | 12 | 285
Cash Paid During the Period for: |  |  |
Interest | 571 | 584 | 660
Income taxes | $ 20 | $ 14 | $ 15

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- Definition Amount of cash (inflow) outflow from investing activities classified as other. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3098-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3095-108585 + Details
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- Definition The cash outflow to reacquire common stock during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585 + Details
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- Definition The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585 + Details
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- Definition The cash outflow associated with the purchase of all investments (debt, security, other) during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585 + Details
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- Definition The cash outflow for purchases of and capital improvements on property, plant and equipment (capital expenditures), software, and other intangible assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585 + Details
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- Definition The cash outflow for securities or other assets acquired, which qualify for treatment as an investing activity and are to be liquidated, if necessary, within the current operating cycle. Includes cash flows from securities classified as trading securities that were acquired for reasons other than sale in the short-term. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585 + Details
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- Definition The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3255-108585 + Details
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- Definition Amount of cash inflow (outflow) from financing activities classified as other. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3095-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3098-108585 + Details
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- Definition The cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3179-108585 + Details
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- Definition Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3255-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=96867065&loc=SL79508275-113901 + Details
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- Definition The cash outflow for the obligation for a lease meeting the criteria for capitalization (with maturities exceeding one year or beyond the operating cycle of the entity, if longer). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585 + Details
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- Definition The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585 + Details
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- Definition Amount, after cash payment, of expenses associated with exit or disposal activities pursuant to an authorized plan and expenses resulting from the write-down of assets. Excludes expenses related to a business combination, a discontinued operation or an asset retirement obligation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585 + Details
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