CSX (CSX) 10-Q 17 Oct 18 2018 Q3 Quarterly report Financial data

Document And Entity Information

Document And Entity Information	9 Months Ended
	Sep. 30, 2018shares
Document and Entity Information [Abstract]
Entity Registrant Name	CSX CORP
Entity Central Index Key	277,948
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding	844,420,361
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q3
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2018
Entity Emerging Growth Company	false
Entity Small Business	false

CONSOLIDATED INCOME STATEMENTS

CONSOLIDATED INCOME STATEMENTS (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Income Statement
Revenues	$ 3,129	$ 2,743	$ 9,107	$ 8,545
Expense
Labor and Fringe	695	725	2,060	2,271
Materials, Supplies and Other	474	523	1,425	1,590
Depreciation	334	331	986	978
Fuel	268	205	793	621
Equipment and Other Rents	89	109	302	313
Restructuring Charge (Note 1)	0	1	0	226
Equity Earnings of Affiliates	(24)	(19)	(79)	(48)
Total Expense	1,836	1,875	5,487	5,951
Operating Income	1,293	868	3,620	2,594
Interest Expense	(162)	(132)	(468)	(406)
Restructuring Charge - Non-Operating (Note 1)	0	0	0	(70)
Other Income - Net	19	14	54	41
Earnings Before Income Taxes	1,150	750	3,206	2,159
Income Tax Expense	(256)	(291)	(740)	(828)
Net Earnings	$ 894	$ 459	$ 2,466	$ 1,331
Per Common Share
Net Earnings Per Share, Basic (in dollars per share)	$ 1.05	$ 0.51	$ 2.85	$ 1.45
Net Earnings Per Share, Assuming Dilution (in dollars per share)	$ 1.05	$ 0.51	$ 2.83	$ 1.45
Average Shares Outstanding (in shares)	850	902	866	916
Average Shares Outstanding, Assuming Dilution (in shares)	854	906	870	919
Cash Dividends Paid Per Common Share (in dollars per share)	$ 0.22	$ 0.20	$ 0.66	$ 0.58

CONSOLIDATED COMPREHENSIVE INCO

CONSOLIDATED COMPREHENSIVE INCOME STATEMENTS (Unaudited) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Statement of Comprehensive Income [Abstract]
Total Comprehensive Earnings (Note 10)	$ 901	$ 467	$ 2,378	$ 1,410

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017	Sep. 30, 2017	Dec. 30, 2016
Current Assets:
Cash and Cash Equivalents	$ 663	$ 401	$ 591	$ 603
Short-term Investments	615	18
Accounts Receivable - Net (Note 11)	1,090	970
Materials and Supplies	283	372
Other Current Assets	133	154
Total Current Assets	2,784	1,915
Properties	44,485	44,324
Accumulated Depreciation	(12,614)	(12,560)
Properties - Net	31,871	31,764
Other Long-term Assets	442	374
Total Assets	36,861	35,739
Current Liabilities:
Accounts Payable	982	847
Labor and Fringe Benefits Payable	517	602
Casualty, Environmental and Other Reserves (Note 4)	110	108
Current Maturities of Long-term Debt (Note 7)	18	19
Income and Other Taxes Payable	166	157
Other Current Liabilities	151	161
Total Current Liabilities	1,944	1,894
Casualty, Environmental and Other Reserves (Note 4)	231	266
Long-term Debt (Note 7)	13,754	11,790
Deferred Income Taxes - Net	6,584	6,418
Other Long-term Liabilities	613	650
Total Liabilities	23,126	21,018
Shareholders' Equity:
Common Stock, $1 Par Value	844	890
Other Capital	129	217
Retained Earnings	13,320	14,084
Accumulated Other Comprehensive Loss (Note 10)	(574)	(486)
Noncontrolling Interest	16	16
Total Shareholders' Equity	13,735	14,721
Total Liabilities and Shareholders' Equity	36,861	35,739
Investments in Conrail
Current Assets:
Investment in Affiliates and Other Companies	941	907
Affiliates and Other Companies
Current Assets:
Investment in Affiliates and Other Companies	$ 823	$ 779

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Sep. 30, 2018	Dec. 31, 2017
Shareholders' Equity:
Common stock, par value (in dollars per share)	$ 1	$ 1

CONSOLIDATED CASH FLOW STATEMEN

CONSOLIDATED CASH FLOW STATEMENTS (Unaudited) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
OPERATING ACTIVITIES
Net Earnings	$ 2,466	$ 1,331
Adjustments to Reconcile Net Earnings to Net Cash Provided by Operating Activities:
Depreciation	986	978
Deferred Income Taxes	148	161
Gain on Property Dispositions	(122)	(5)
Equity Earnings of Affiliates	(79)	(48)
Restructuring Charge	0	296
Cash Payments for Restructuring Charge	(14)	(147)
Other Operating Activities	(13)	40
Changes in Operating Assets and Liabilities:
Accounts Receivable	(97)	(78)
Other Current Assets	70	47
Accounts Payable	140	102
Income and Other Taxes Payable	19	180
Other Current Liabilities	(98)	4
Net Cash Provided by Operating Activities	3,406	2,861
INVESTING ACTIVITIES
Property Additions	(1,240)	(1,462)
Proceeds from Property Dispositions	257	38
Purchase of Short-term Investments	(611)	(645)
Proceeds from Sales of Short-term Investments	15	957
Other Investing Activities	(8)	33
Net Cash Used In Investing Activities	(1,587)	(1,079)
FINANCING ACTIVITIES
Long-term Debt Issued (Note 7)	2,000	850
Long-term Debt Repaid (Note 7)	(19)	(332)
Dividends Paid	(570)	(530)
Shares Repurchased	(2,816)	(1,763)
Accelerated Share Repurchase Pending Final Settlement (Note 2)	(100)	0
Other Financing Activities	(52)	(19)
Net Cash Used in Financing Activities	(1,557)	(1,794)
Net Increase (Decrease) in Cash and Cash Equivalents	262	(12)
CASH AND CASH EQUIVALENTS
Cash and Cash Equivalents at Beginning of Period	401	603
Cash and Cash Equivalents at End of Period	$ 663	$ 591

Nature of Operations and Signif

Nature of Operations and Significant Accounting Policies	9 Months Ended
	Sep. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Operations and Significant Accounting Policies	Nature of Operations and Significant Accounting Policies Background CSX Corporation (“CSX”), together with its subsidiaries (the “Company”), based in Jacksonville, Florida, is one of the nation's leading transportation companies. The Company provides rail-based transportation services including traditional rail service and the transport of intermodal containers and trailers. CSX's principal operating subsidiary, CSX Transportation, Inc. (“CSXT”), provides an important link to the transportation supply chain through its approximately 21,000 route mile rail network, which serves major population centers in 23 states east of the Mississippi River, the District of Columbia and the Canadian provinces of Ontario and Quebec. The Company's intermodal business links customers to railroads via trucks and terminals. After a merger on July 1, 2017 with CSX Real Property, Inc., a former wholly-owned CSX subsidiary, CSXT is now responsible for the Company's real estate sales, leasing, acquisition and management and development activities. In addition, as substantially all real estate sales, leasing, acquisition and management and development activities are focused on supporting railroad operations, all results of these activities are included in operating income beginning in 2017. Previously, the results of these activities were classified as operating or non-operating based on the nature of the activity and were not material for any periods presented. Other entities In addition to CSXT, the Company’s subsidiaries include CSX Intermodal Terminals, Inc. (“CSX Intermodal Terminals”), Total Distribution Services, Inc. (“TDSI”), Transflo Terminal Services, Inc. (“Transflo”), CSX Technology, Inc. (“CSX Technology”) and other subsidiaries. CSX Intermodal Terminals owns and operates a system of intermodal terminals, predominantly in the eastern United States and also performs drayage services (the pickup and delivery of intermodal shipments) for certain customers and trucking dispatch operations. TDSI serves the automotive industry with distribution centers and storage locations. Transflo connects non-rail served customers to the many benefits of rail by transferring products from rail to trucks. The biggest Transflo markets are chemicals and agriculture, which include shipments of plastics and ethanol. CSX Technology and other subsidiaries provide support services for the Company. Basis of Presentation In the opinion of management, the accompanying consolidated financial statements contain all normal, recurring adjustments necessary to fairly present the following: • Consolidated income statements for the quarter and nine months ended September 30, 2018 and September 30, 2017 ; • Condensed consolidated comprehensive income statements for the quarter and nine months ended September 30, 2018 and September 30, 2017 ; • Consolidated balance sheets at September 30, 2018 and December 31, 2017 ; and • Consolidated cash flow statements for the nine months ended September 30, 2018 and September 30, 2017 . NOTE 1. Nature of Operations and Significant Accounting Policies, continued Pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”), certain information and disclosures normally included in the notes to the annual financial statements prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) have been omitted from these interim financial statements. CSX suggests that these financial statements be read in conjunction with the audited financial statements and the notes included in CSX's most recent annual report on Form 10-K and any subsequently filed current reports on Form 8-K. Fiscal Year Through the second quarter 2017, CSX followed a 52/53 week fiscal reporting calendar with the last day of each reporting period ending on a Friday. On July 7, 2017 the Board of Directors of CSX approved a change in the fiscal reporting calendar from a 52/53 week year ending on the last Friday of December to a calendar year ending on December 31 each year, effective beginning with fiscal third quarter 2017. Related to the change in the fiscal calendar: • Fiscal year 2018 (January 1, 2018 through December 31, 2018) will contain 365 days, and fiscal year 2017 (December 31, 2016 through December 31, 2017) contained 366 days. • Fiscal first quarter 2018 (January 1, 2018 through March 31, 2018) contained 90 days, and fiscal first quarter 2017 (December 31, 2016 through March 31, 2017) contained 91 days. • Fiscal second quarter 2018 (April 1, 2018 through June 30, 2018) contained 91 days, and fiscal second quarter 2017 (April 1, 2017 through June 30, 2017) contained 91 days. • Fiscal third quarter 2018 (July 1, 2018 through September 30, 2018) contained 92 days, and fiscal third quarter 2017 (July 1, 2017 through September 30, 2017) contained 92 days. This change did not materially impact the comparability of the Company’s financial results. Accordingly, the change to a calendar fiscal year was made on a prospective basis and operating results for prior periods were not adjusted. The Company was not required to file a transition report because this change was not deemed a change in fiscal year for purposes of reporting subject to Rule 13a-10 or Rule 15d-10 of the Securities Exchange Act of 1934 as the new fiscal year commenced with the end of the prior fiscal year end and within seven days of the prior fiscal year end. Except as otherwise specified, references to “ third quarter(s)” or “ nine months” indicate CSX's fiscal periods ending September 30, 2018 and September 30, 2017 , and references to "year-end" indicate the fiscal year ended December 31, 2017 . New Accounting Pronouncements Pronouncements adopted in 2018 In February 2018, the Financial Accounting Standards Board ("FASB") issued Accounting Standard Update ("ASU") Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Inco me, which permits entities to reclassify tax effects stranded in accumulated other comprehensive income as a result of tax reform to retained earnings. Companies that elect to reclassify these amounts must reclassify stranded tax effects for all items accounted for in accumulated other comprehensive income. The Company adopted this standard update in first quarter 2018 and applied it prospectively. Adoption resulted in the reclassification of $107 million in tax effects related to employee benefit plans from accumulated other comprehensive loss, increasing retained earnings by the same amount. NOTE 1. Nature of Operations and Significant Accounting Policies, continued In March 2017, the FASB issued ASU Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost , which requires that only the service cost component of net periodic benefit costs be recorded as compensation cost in operating expense on the consolidated income statement. All other components of net periodic benefit cost (interest cost, expected return on plan assets, amortization of net loss, special termination benefits and settlement and curtailment effects) should be presented as non-operating charges on the consolidated income statement. If these non-operating charges are related to prior year restructuring activities, they are presented as restructuring charge - non-operating. Other non-operating charges are presented as other income - net. The Company adopted the provisions of this standard during first quarter 2018 and applied them retrospectively. The retrospective impact of adoption for third quarter and nine months 2017 is shown in the following table. Third Quarter 2017 Nine Months 2017 (Dollars in millions) As Previously Reported Reclass As Reclassified As Previously Reported Reclass As Reclassified Operating Expense: Labor and Fringe $ 717 $ 8 $ 725 $ 2,249 $ 22 $ 2,271 Restructuring Charge 1 — 1 296 (70 ) 226 Non-Operating Income (Expense): Restructuring Charge - Non-Operating $ — $ — $ — $ — $ (70 ) $ (70 ) Other Income - Net 6 8 14 19 22 41 In May 2014, the FASB issued ASU Revenue from Contracts with Customers , which supersedes previous revenue recognition guidance. The new standard requires that a company recognize revenue when it transfers promised goods or services to customers in an amount that reflects the consideration the company expects to receive in exchange for those goods or services. In-depth reviews of commercial contracts were completed and changes to processes and internal controls to meet the standard’s reporting and disclosure requirements were implemented. The Company adopted the guidance effective January 1, 2018 using the modified retrospective approach. The adoption did not affect the Company’s financial condition, results of operations or liquidity. Disclosures related to the nature, amount and timing of revenue and cash flows arising from contracts with customers are included in Note 11, Revenues. Pronouncements to be adopted In February 2016, the FASB issued ASU, Leases , which will require lessees to recognize most leases on their balance sheets as a right-of-use asset with a corresponding lease liability, and lessors to recognize a net lease investment. Additional qualitative and quantitative disclosures will also be required. This standard update is effective for CSX beginning with the first quarter 2019 and the Company plans to adopt it using the cumulative-effect adjustment transition method approved by the FASB in July 2018. Changes to processes and internal controls to meet the standard’s reporting and disclosure requirements have been identified and are being implemented. Software has been implemented that will assist in the recognition of additional assets and liabilities to be included on the balance sheet related to leases currently classified as operating leases with durations greater than twelve months, with certain allowable exceptions. In addition to lease agreements, service contracts and other agreements are also being reviewed to determine if they contain an embedded lease. The Company continues to evaluate the expected impact of this standard update on disclosures, but does not anticipate any material changes to operating results or liquidity as a result of right-of-use assets and corresponding lease liabilities that will be recorded. NOTE 1. Nature of Operations and Significant Accounting Policies, continued In January 2018, the FASB issued ASU Leases - Land Easement Practical Expedient , which permits entities to forgo the evaluation of existing land easement arrangements to determine if they contain a lease as part of the adoption of the Leases ASU issued in February 2016. Accordingly, the Company’s accounting treatment of existing land easements will not change. CSX will adopt this standard update concurrently with the Leases ASU issued in February 2016. New land easement arrangements, or modifications to existing arrangements, after the adoption of the standard update will still be evaluated to determine if they meet the definition of a lease. In March 2017, the FASB issued ASU Simplifying the Test for Goodwill Impairment, which eliminates step two, the calculation of the implied fair value of goodwill, from the goodwill impairment test. Impairment will be quantified in step one of the test as the amount by which the carrying amount exceeds the fair value. This standard update is effective beginning first quarter 2020 and must be applied prospectively. The Company does not believe this standard update will have a material effect on its financial condition, results of operations or liquidity. Restructuring Charge The prior year restructuring charge includes costs related to the management workforce reduction program completed in 2017, reimbursement arrangements with MR Argent Advisor LLC (“Mantle Ridge”) and the Company’s former President and Chief Executive Officer, E. Hunter Harrison, the proration of equity awards and other advisory costs related to the leadership transition. Payments related to the 2017 restructuring charge were substantially complete as of March 31, 2018. For further details on the charge, see the Company's most recent annual report on Form 10-K. During third quarter 2017, restructuring charge of $1 million was incurred for advisory fees related to shareholder matters. Expenses related to the management workforce reduction and other costs during the nine months 2017 are shown in the following table. Nine Months 2017 (Dollars in millions) As Previously Reported Operating Restructuring Charge Non-Operating Restructuring Charge Severance and Pension $ 144 $ 91 $ 53 Other Post-Retirement Benefits Curtailment 17 — 17 Employee Equity Awards Proration and Other 16 16 — Subtotal Management Workforce Reduction $ 177 $ 107 $ 70 Reimbursement Arrangements 84 84 — Executive Equity Awards Proration 24 24 — Advisory Fees Related to Shareholder Matters 11 11 — Total Restructuring Charge $ 296 $ 226 $ 70

Earnings Per Share

Earnings Per Share	9 Months Ended
	Sep. 30, 2018
Earnings Per Share [Abstract]
Earnings Per Share	Earnings Per Share The following table sets forth the computation of basic earnings per share and earnings per share, assuming dilution: Third Quarters Nine Months 2018 2017 2018 2017 Numerator (Dollars in millions) : Net Earnings $ 894 $ 459 $ 2,466 $ 1,331 Dividend Equivalents on Restricted Stock — — — (1 ) Net Earnings, Attributable to Common Shareholders $ 894 $ 459 $ 2,466 $ 1,330 Denominator (Units in millions) : Average Common Shares Outstanding 850 902 866 916 Other Potentially Dilutive Common Shares 4 4 4 3 Average Common Shares Outstanding, Assuming Dilution 854 906 870 919 Net Earnings Per Share, Basic $ 1.05 $ 0.51 $ 2.85 $ 1.45 Net Earnings Per Share, Assuming Dilution $ 1.05 $ 0.51 $ 2.83 $ 1.45 Basic earnings per share is based on the weighted-average number of shares of common stock outstanding. Earnings per share, assuming dilution, is based on the weighted-average number of shares of common stock equivalents outstanding adjusted for the effects of common stock that may be issued as a result of potentially dilutive instruments. CSX's potentially dilutive instruments are made up of equity awards, which include long-term incentive awards and employee stock options. The Earnings Per Share Topic in the FASB's ASC requires CSX to include additional shares in the computation of earnings per share, assuming dilution. The additional shares included in diluted earnings per share represent the number of shares that would be issued if all of the above potentially dilutive instruments were converted into CSX common stock. When calculating diluted earnings per share, this rule requires CSX to include the potential shares that would be outstanding if all outstanding stock options were exercised. This number is different from outstanding stock options because it is offset by shares CSX could repurchase using the proceeds from these hypothetical exercises to obtain the common stock equivalent. Approximately seven thousand and 10 million of total average outstanding stock options for the third quarters ended September 30, 2018 and September 30, 2017 , respectively, were excluded from the diluted earnings per share calculation because their effect was antidilutive. NOTE 2. Earnings Per Share, continued Share Repurchases In February 2018, the Company announced an increase to the $1.5 billion share repurchase program first announced in October 2017, bringing the total authorized to $5 billion . This program is expected to be completed by the end of first quarter 2019. During the third quarters of 2018 and 2017 , the Company repurchased approximately $1.0 billion , or 15 million shares, and $1.0 billion , or 20 million shares, respectively. During the nine months of 2018 and 2017, the Company repurchased $2.8 billion , or 46 million shares, and $1.8 billion , or 35 million shares, respectively. On July 19, 2018, the Company entered into an accelerated share repurchase agreement to repurchase shares of the Company’s common stock. Under this agreement, the Company made a prepayment of $500 million to a financial institution and received an initial delivery of 6 million shares valued at $400 million . The remaining balance of $100 million was settled through receipt of additional shares on October 11, 2018, with the final net number of shares calculated based on the volume-weighted average price of the Company's common stock over the term of the agreement, less a discount. Approximately 7 million total shares were repurchased under the agreement. Under an accelerated share repurchase agreement executed in April 2018, the Company made a prepayment of $450 million to a financial institution and received an initial delivery of 6 million shares valued at $360 million . The remaining balance of $90 million was settled through receipt of additional shares in July 2018, with the final net number of shares calculated based on the volume-weighted average price of the Company's common stock over the term of the agreement, less a discount. Approximately 7 million total shares were repurchased under the agreement. Under an accelerated share repurchase agreement executed in January 2018, the Company made a prepayment of $150 million to a financial institution and received an initial delivery of shares valued at $120 million . The remaining balance of $30 million was settled through receipt of additional shares in February 2018 with the final net number of shares calculated based on the volume-weighted average price of the Company's common stock over the term of the agreement, less a discount. Approximately 3 million total shares were repurchased under the agreement. Management's assessment of market conditions and other factors guides the timing and volume of repurchases. Future share repurchases are expected to be funded by cash on hand, cash generated from operations and debt issuances. Shares are retired immediately upon repurchase. In accordance with the Equity Topic in the ASC, the excess of repurchase price over par value is recorded in retained earnings.

Share-Based Compensation

Share-Based Compensation	9 Months Ended
	Sep. 30, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Share-Based Compensation	Share-Based Compensation Under CSX's share-based compensation plans, awards consist of performance units, restricted stock awards, restricted stock units and stock options for management and stock grants for directors. Awards granted under the various programs are determined and approved by the Compensation Committee of the Board of Directors or, in certain circumstances, by the Chief Executive Officer for awards to management employees other than senior executives. The Board of Directors approves awards granted to CSX's non-management directors upon recommendation of the Governance Committee. In May 2018, shareholders approved the 2018 CSX Employee Stock Purchase Plan (“ESPP”) for the benefit of Company employees. The Company registered 4 million shares of common stock that may be issued pursuant to this plan. Under the ESPP, employees may contribute between 1% and 10% of base compensation, after-tax, to purchase up to $25,000 of CSX common stock per year. No shares will be issued under the ESPP until first quarter 2019. Share-based compensation expense is measured using the fair value of the award on the grant date and is recognized on a straight-line basis over the service period of the respective award. Total pre-tax expense associated with share-based compensation and its related income tax benefit is shown in the table below. The year over year decrease in third quarter share-based compensation expense is primarily due to the prior year expense related to 9 million stock options granted in February 2017 to former President and CEO E. Hunter Harrison, which were forfeited upon his death in December 2017. Additionally, the decrease in nine months expense was also due to modifications to the terms of awards in the first and second quarters of 2017 (see Equity Award Modifications below). Third Quarters Nine Months (Dollars in millions) 2018 2017 2018 2017 Share-Based Compensation Expense: Performance Units $ 8 $ 3 $ 22 $ 41 Stock Options 4 14 10 47 Restricted Stock Units and Awards 1 2 4 11 Stock Awards for Directors — — 2 2 Total Share-Based Compensation Expense $ 13 $ 19 $ 38 $ 101 Income Tax Benefit $ 6 $ 12 $ 23 $ 41 Long-term Incentive Plan In February 2018 , the Company granted approximately 350 thousand performance units to certain employees under a new long-term incentive plan ("LTIP") for the years 2018 through 2020, which was adopted under the CSX Stock and Incentive Award Plan. During third quarter 2018, there were immaterial grants of performance units to certain members of management. No performance units were granted during third quarter 2017. Payouts of performance units for the cycle ending with fiscal year 2020 will be based on the achievement of goals related to both operating ratio and free cash flow, in each case excluding non-recurring items as disclosed in the Company's financial statements. The final year operating ratio and cumulative free cash flow over the plan period will each comprise 50% of the payout and will be measured independently of the other. NOTE 3. Share-Based Compensation, continued Grants were made in performance units, with each unit representing the right to receive one share of CSX common stock, and payouts will be made in CSX common stock. The payout range for participants will be between 0% and 200% of the target awards depending on Company performance against predetermined goals. Payouts for certain executive officers are subject to upward or downward adjustment by up to 25% , capped at an overall payout of 200% , based upon the Company's total shareholder return relative to specified comparable groups over the performance period. The fair value of the performance units awarded during the quarter and nine months ended September 30, 2018 was calculated using a Monte-Carlo simulation model with the following weighted-average assumptions: Third Quarter Nine Months 2018 2018 Weighted-average assumptions used: Annual dividend yield 1.2 % 1.6 % Risk-free interest rate 2.7 % 2.3 % Annualized volatility 27.9 % 29.1 % Expected life (in years) 2.3 2.9 Stock Options Also, in February 2018 , the Company granted approximately 950 thousand stock options along with the corresponding LTIP. The fair value of stock options on the date of grant was $14.55 per option which was calculated using the Black-Scholes valuation model. Stock options have been granted with ten -year terms and vest three years after the date of grant. The exercise price for stock options granted equals the closing market price of the underlying stock on the date of grant. These awards are time-based and are not based upon attainment of performance goals. During third quarter 2018, there were immaterial grants of stock options to certain members of management. No stock options awards were granted during third quarter 2017. The fair values of all stock option awards during the quarter and nine months ended September 30, 2018 and September 30, 2017 were estimated at the grant date with the following weighted average assumptions: Third Quarters Nine Months 2018 2017 2018 2017 Weighted-average grant date fair value $ 20.52 $ — $ 14.65 $ 12.83 Stock options valuation assumptions: Annual dividend yield 1.2 % — % 1.5 % 1.5 % Risk-free interest rate 2.8 % — % 2.6 % 2.2 % Annualized volatility 25.5 % — % 27.0 % 27.1 % Expected life (in years) 6.5 — 6.5 6.3 Other pricing model inputs: Weighted-average grant-date market price of CSX stock (strike price) $ 74.84 $ — $ 54.19 $ 49.60 NOTE 3. Share-Based Compensation, continued Restricted Stock Units Finally, in February 2018, the Company granted approximately 85 thousand restricted stock units along with the corresponding LTIP. The restricted stock units vest three years after the date of grant. Participants receive cash dividend equivalents on the unvested shares during the restriction period. These awards are time-based and are not based upon attainment of performance goals. For information related to the Company's other outstanding long-term incentive compensation, see CSX's most recent annual report on Form 10-K. During third quarter 2018, there were immaterial grants of restricted stock units to certain members of management. No restricted stock units were granted during third quarter 2017. Equity Award Modifications In 2017, as part of an enhanced severance benefit under the management streamlining and realignment initiative discussed in Note 1, unvested performance units, restricted stock units and stock options for separated employees not eligible for retirement were permitted to vest on a pro-rata basis. Additionally, the terms of unvested equity awards for the former Chief Executive Officer, Michael J. Ward, and former President, Clarence W. Gooden, were modified prior to their retirements on March 6, 2017 to permit prorated vesting through May 31, 2018. These award modifications impacted approximately 70 employees and resulted in an increase to share-based compensation expense for revaluation of the affected awards of $31 million for the nine months ended September 30, 2017. The expense associated with these award modifications was included in the 2017 restructuring charge. No significant award modifications took place in 2018 or in third quarter 2017.

Casualty, Environmental and Oth

Casualty, Environmental and Other Reserves	9 Months Ended
	Sep. 30, 2018
Casualty, Environmental and Other Reserves [Abstract]
Casualty, Environmental and Other Reserves	Casualty, Environmental and Other Reserves Personal injury and environmental reserves are considered critical accounting estimates due to the need for significant management judgment. Casualty, environmental and other reserves are provided for in the consolidated balance sheets as shown in the table below. September 30, 2018 December 31, 2017 (Dollars in millions) Current Long-term Total Current Long-term Total Casualty: Personal Injury $ 42 $ 108 $ 150 $ 43 $ 125 $ 168 Occupational 7 47 54 6 54 60 Total Casualty 49 155 204 49 179 228 Environmental 37 52 89 31 59 90 Other 24 24 48 28 28 56 Total $ 110 $ 231 $ 341 $ 108 $ 266 $ 374 These liabilities are accrued when reasonably estimable and probable in accordance with the Contingencies Topic in the ASC. Actual settlements and claims received could differ, and final outcomes of these matters cannot be predicted with certainty. Considering the legal defenses currently available, the liabilities that have been recorded and other factors, it is the opinion of management that none of these items individually, when finally resolved, will have a material adverse effect on the Company's financial condition, results of operations or liquidity. Should a number of these items occur in the same period, however, their combined effect could be material in that particular period. NOTE 4. Casualty, Environmental and Other Reserves, continued Casualty Casualty reserves of $204 million and $228 million as of September 30, 2018 and December 31, 2017 , respectively, represent accruals for personal injury, occupational disease and occupational injury claims. During second quarter 2018, the Company increased its self-insured retention amount for these claims from $ 50 million to $75 million per occurrence for claims occurring on or after June 1, 2018. Currently, no individual claim is expected to exceed the self-insured retention amount. In accordance with the Contingencies Topic in the ASC, to the extent the value of an individual claim exceeds the self-insured retention amount, the Company would present the liability on a gross basis with a corresponding receivable for insurance recoveries. These reserves fluctuate based upon the timing of payments as well as changes in estimate. Actual results may vary from estimates due to the number, type and severity of the injury, costs of medical treatments and uncertainties in litigation. Most of the Company's casualty claims relate to CSXT unless otherwise noted below. Defense and processing costs, which historically have been insignificant and are anticipated to be insignificant in the future, are not included in the recorded liabilities. Personal Injury Personal injury reserves represent liabilities for employee work-related and third-party injuries. Work-related injuries for CSXT employees are primarily subject to the Federal Employers’ Liability Act (“FELA”). CSXT retains an independent actuary to assist management in assessing the value of personal injury claims. An analysis is performed by the actuary quarterly and is reviewed by management. This analysis for the quarter resulted in an immaterial adjustment to the personal injury reserve. The methodology used by the actuary includes a development factor to reflect growth or reduction in the value of these personal injury claims based largely on CSXT's historical claims and settlement experience. Occupational Occupational reserves represent liabilities for occupational disease and injury claims. Occupational disease claims arise primarily from allegations of exposure to asbestos in the workplace. Occupational injury claims arise from allegations of exposure to certain other materials in the workplace, such as solvents, soaps, chemicals (collectively referred to as “irritants”) and diesel fuels (like exhaust fumes) or allegations of chronic physical injuries resulting from work conditions, such as repetitive stress injuries. Environmental Environmental reserves were $89 million and $90 million as of September 30, 2018 and December 31, 2017 , respectively. The Company is a party to various proceedings related to environmental issues, including administrative and judicial proceedings involving private parties and regulatory agencies. The Company has been identified as a potentially responsible party at approximately 216 environmentally impaired sites. Many of these are, or may be, subject to remedial action under the federal Comprehensive Environmental Response, Compensation and Liability Act of 1980 ("CERCLA"), also known as the Superfund Law, or similar state statutes. Most of these proceedings arose from environmental conditions on properties used for ongoing or discontinued railroad operations. A number of these proceedings, however, are based on allegations that the Company, or its predecessors, sent hazardous substances to facilities owned or operated by others for treatment, recycling or disposal. In addition, some of the Company's land holdings were leased to others for commercial or industrial uses that may have resulted in releases of hazardous substances or other regulated materials onto the property and could give rise to proceedings against the Company. NOTE 4. Casualty, Environmental and Other Reserves, continued In any such proceedings, the Company is subject to environmental clean-up and enforcement actions under the Superfund Law, as well as similar state laws that may impose joint and several liability for clean-up and enforcement costs on current and former owners and operators of a site without regard to fault or the legality of the original conduct. These costs could be substantial. In accordance with the Asset Retirement and Environmental Obligations Topic in the ASC, the Company reviews its role with respect to each site identified at least quarterly, giving consideration to a number of factors such as: • type of clean-up required; • nature of the Company's alleged connection to the location (e.g., generator of waste sent to the site or owner or operator of the site); • extent of the Company's alleged connection (e.g., volume of waste sent to the location and other relevant factors); and • number, connection and financial viability of other named and unnamed potentially responsible parties at the location. Based on the review process, the Company has recorded amounts to cover contingent anticipated future environmental remediation costs with respect to each site to the extent such costs are reasonably estimable and probable. The recorded liabilities for estimated future environmental costs are undiscounted. The liability includes future costs for remediation and restoration of sites as well as any significant ongoing monitoring costs, but excludes any anticipated insurance recoveries. Payments related to these liabilities are expected to be made over the next several years. Environmental remediation costs are included in materials, supplies and other on the consolidated income statements. Currently, the Company does not possess sufficient information to reasonably estimate the amounts of additional liabilities, if any, on some sites until completion of future environmental studies. In addition, conditions that are currently unknown could, at any given location, result in additional exposure, the amount and materiality of which cannot presently be reasonably estimated. Based upon information currently available, however, the Company believes its environmental reserves accurately reflect the estimated cost of remedial actions currently required. Other Other reserves of $48 million and $56 million as of September 30, 2018 and December 31, 2017 , respectively, include liabilities for various claims, such as property, automobile and general liability. Also included in other reserves are longshoremen disability claims related to a previously owned international shipping business (these claims are in runoff) as well as claims for current port employees.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Insurance The Company maintains numerous insurance programs with substantial limits for property damage (which includes business interruption) and third-party liability. A certain amount of risk is retained by the Company on each of the property and liability programs. The Company has a $50 million per occurrence retention for floods and named windstorms and a $ 25 million per occurrence retention for property losses other than floods and named windstorms. For claims occurring on or after June 1, 2018, the Company increased its self-insured retention for third-party liability claims from $ 50 million to $75 million per occurrence. While the Company believes its insurance coverage is adequate, future claims could exceed existing insurance coverage or insurance may not continue to be available at commercially reasonable rates. Legal The Company is involved in litigation incidental to its business and is a party to a number of legal actions and claims, various governmental proceedings and private civil lawsuits, including, but not limited to, those related to fuel surcharge practices, tax matters, environmental and hazardous material exposure matters, FELA and labor claims by current or former employees, other personal injury or property claims and disputes and complaints involving certain transportation rates and charges. Some of the legal proceedings include claims for compensatory as well as punitive damages and others are, or are purported to be, class actions. While the final outcome of these matters cannot be reasonably determined, considering, among other things, the legal defenses available and liabilities that have been recorded along with applicable insurance, it is currently the opinion of management that none of these pending items is likely to have a material adverse effect on the Company's financial condition, results of operations or liquidity. An unexpected adverse resolution of one or more of these items, however, could have a material adverse effect on the Company's financial condition, results of operations or liquidity in that particular period. The Company is able to estimate a range of possible loss for certain legal proceedings for which a loss is reasonably possible in excess of reserves established. The Company has estimated this range to be $2 million to $118 million in aggregate at September 30, 2018 . This estimated aggregate range is based upon currently available information and is subject to significant judgment and a variety of assumptions. Accordingly, the Company's estimate will change from time to time, and actual losses may vary significantly from the current estimate. Fuel Surcharge Antitrust Litigation In May 2007, class action lawsuits were filed against CSXT and three other U.S.-based Class I railroads alleging that the defendants' fuel surcharge practices relating to contract and unregulated traffic resulted from an illegal conspiracy in violation of antitrust laws. In November 2007, the class action lawsuits were consolidated in federal court in the District of Columbia, where they are now pending. The suit seeks treble damages allegedly sustained by purported class members as well as attorneys' fees and other relief. Plaintiffs are expected to allege damages at least equal to the fuel surcharges at issue. NOTE 5. Commitments and Contingencies, continued In June 2012, the District Court certified the case as a class action. The decision was not a ruling on the merits of plaintiffs' claims, but rather a decision to allow the plaintiffs to seek to prove the case as a class. The defendant railroads petitioned the U.S. Court of Appeals for the D.C. Circuit for permission to appeal the District Court's class certification decision. In August 2013, the D.C. Circuit issued a decision vacating the class certification decision and remanded the case to the District Court to reconsider its class certification decision. On October 10, 2017, the District Court issued an order denying class certification. The U.S. Court of Appeals for the D.C. Circuit is reviewing the District Court's denial of class certification and held oral argument on September 28, 2018, with a decision yet to be issued. The District Court has delayed proceedings on the merits of the case pending the outcome of the class certification proceedings. CSXT believes that its fuel surcharge practices were arrived at and applied lawfully and that the case is without merit. Accordingly, the Company intends to defend itself vigorously. However, penalties for violating antitrust laws can be severe, and resolution of this matter or an unexpected adverse decision on the merits could have a material adverse effect on the Company's financial condition, results of operations or liquidity in that particular period. Environmental CSXT is indemnifying Pharmacia LLC (formerly known as Monsanto Company) for certain liabilities associated with real estate located in Kearny, New Jersey along the Lower Passaic River (the “Property”). The Property, which was formerly owned by Pharmacia, is now owned by CSXT. CSXT's indemnification and defense duties arise with respect to several matters. The U.S. Environmental Protection Agency ("EPA"), using its CERCLA authority, seeks cleanup and removal costs and other damages associated with the presence of hazardous substances in the 17 -mile Lower Passaic River Study Area (the "Study Area”). CSXT, on behalf of Pharmacia, and a significant number of other potentially responsible parties are together conducting a Remedial Investigation and Feasibility Study of the Study Area pursuant to an Administrative Settlement Agreement and Order on Consent with the EPA. In March 2016, EPA issued its Record of Decision detailing the agency’s mandated remedial process for the lower 8 miles of the Study Area. Approximately 80 parties, including Pharmacia, are participating in an EPA-directed allocation process to assign responsibility for costs to be incurred implementing the remedy selected for the lower 8 miles of the Study Area. CSXT is participating in the allocation process on behalf of Pharmacia. At a later date, EPA will select a remedy for the remainder of the Study Area and is expected to again seek the participation of private parties to implement the selected remedy using EPA’s CERCLA authority to compel such participation, if necessary. CSXT is also defending and indemnifying Pharmacia in a cooperative natural resource damages assessment process related to the Property. Based on currently available information, the Company does not believe any indemnification or remediation costs potentially allocable to CSXT with respect to the Property and the Study Area would be material to the Company's financial condition, results of operations or liquidity.

Employee Benefit Plans

Employee Benefit Plans	9 Months Ended
	Sep. 30, 2018
Retirement Benefits [Abstract]
Employee Benefit Plans	Employee Benefit Plans The Company sponsors defined benefit pension plans principally for salaried, management personnel. CSX also sponsors a post-retirement medical plan and a life insurance plan that provide certain benefits to eligible employees hired prior to January 1, 2003. Independent actuaries compute the amounts of liabilities and expenses relating to these plans subject to the assumptions that the Company determines are appropriate based on historical trends, current market rates and future projections. These amounts are reviewed by management. Only the service cost component of net periodic benefit costs is included in labor and fringe expense on the consolidated income statement. All other components of net periodic benefit cost are included in other income - net or, if related to prior year restructuring activities, in restructuring charge - non-operating. Pension Benefits (Dollars in millions) Third Quarters Nine Months 2018 2017 2018 2017 Service Cost Included in Labor and Fringe $ 8 $ 8 $ 24 $ 28 Interest Cost 23 23 69 69 Expected Return on Plan Assets (44 ) (43 ) (131 ) (128 ) Amortization of Net Loss 10 10 30 31 Total Income Included in Other Income - Net (11 ) (10 ) (32 ) (28 ) Net Periodic Benefit Cost $ (3 ) $ (2 ) $ (8 ) $ — Restructuring Charges - Non Operating (a) — — — 57 Total (Income) Expense $ (3 ) $ (2 ) $ (8 ) $ 57 Other Post-retirement Benefits (Dollars in millions) Third Quarters Nine Months 2018 2017 2018 2017 Service Cost Included in Labor and Fringe $ — $ — $ 1 $ 1 Interest Cost 2 2 5 6 Total Expense Included in Other Income - Net 2 2 5 6 Net Periodic Benefit Cost $ 2 $ 2 $ 6 $ 7 Restructuring Charges - Non Operating (a) — — — 13 Total Expense $ 2 $ 2 $ 6 $ 20 (a) Charges related to special termination benefits and curtailment costs were the result of the management workforce reductions in first quarter 2017. See Restructuring Charge in Note 1, Nature of Operations and Significant Accounting Policies. Qualified pension plan obligations are funded in accordance with regulatory requirements and with an objective of meeting or exceeding minimum funding requirements necessary to avoid restrictions on flexibility of plan operation and benefit payments. No contributions to the Company's qualified pension plans are required in 2018 .

Debt and Credit Agreements

Debt and Credit Agreements	9 Months Ended
	Sep. 30, 2018
Debt Disclosure [Abstract]
Debt and Credit Agreements	Debt and Credit Agreements Total activity related to long-term debt as of the end of third quarter 2018 is shown in the table below. For fair value information related to the Company's long-term debt, see Note 9, Fair Value Measurements. (Dollars in millions) Current Portion Long-term Portion Total Long-term debt as of December 31, 2017 $ 19 $ 11,790 $ 11,809 2018 activity: Long-term debt issued — 2,000 2,000 Long-term debt repaid (19 ) — (19 ) Reclassifications 18 (18 ) — Discount, premium and other activity — (18 ) (18 ) Long-term debt as of September 30, 2018 $ 18 $ 13,754 $ 13,772 Debt Issuance On February 20, 2018, CSX issued $800 million of 3.80% notes due 2028 , $850 million of 4.30% notes due 2048 , and $350 million of 4.65% notes due 2068 . These notes are included in the consolidated balance sheets under long-term debt and may be redeemed by the Company at any time, subject to payment of certain make-whole premiums. The net proceeds will be used for general corporate purposes, which may include repurchases of CSX's common stock, capital investment, working capital requirements, improvements in productivity and other cost reductions at the Company’s major transportation units. Commercial Paper On September 14, 2018, the Company established a commercial paper program, backed by the revolving credit facility, under which the Company may issue unsecured commercial paper notes up to a maximum aggregate principal amount of $1.0 billion outstanding at any one time. Proceeds from issuances of the notes are expected to be used for general corporate purposes. At September 30, 2018, the Company had no outstanding debt under the commercial paper program. Credit Facility CSX has a $1.0 billion unsecured, revolving credit facility backed by a diverse syndicate of banks. The facility allows same-day borrowings at floating (LIBOR-based) interest rates, plus a spread, depending upon CSX's senior unsecured debt ratings. LIBOR is the London Interbank Offered Rate which is a daily reference rate based on the interest rates at which banks offer to lend unsecured funds. This facility expires in May 2020 , and at September 30, 2018, the Company had no outstanding balances under this facility. Commitment fees and interest rates payable under the facility were similar to fees and rates available to comparably rated investment-grade borrowers. As of third quarter 2018 , CSX was in compliance with all covenant requirements under this facility. Receivables Securitization Facility The Company has a receivables securitization facility with a three -year term scheduled to expire in September 2019 . The purpose of this facility is to provide a low cost source of short-term liquidity of up to $200 million , depending on eligible receivables balances. At September 30, 2018, the Company had no outstanding balances under this facility.

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2018
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The effective tax rate decreased to 23.1% from 38.4% for the nine months ended September 30, 2018 and September 30, 2017, respectively, primarily as a result of the significant reduction in the federal corporate income tax rate effective January 1, 2018. During third quarter 2018, the Company filed its 2017 Federal Income Tax return which resulted in an immaterial adjustment to the deferred tax liability and tax expense. Accordingly, the Company's accounting for the federal rate reduction under the Tax Cuts and Jobs Act (“the Act”) is now complete. The Act has significant complexity and implementation guidance from the Internal Revenue Service and clarifications of state tax law, among other things, could impact the Company's accounting for provisions of the Act other than the federal rate reduction within the measurement period as defined in the SEC's Staff Accounting Bulletin No. 118 ("SAB 118"). As such, any resulting potential adjustments within the measurement period remain open under SAB 118. The Company does not believe potential adjustments in future periods would materially impact its financial condition or results of operations. There have been no material changes to the balance of unrecognized tax benefits reported at December 31, 2017 .

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2018
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements The Financial Instruments Topic in the ASC requires disclosures about fair value of financial instruments in annual reports as well as in quarterly reports. For CSX, this statement applies to certain investments and long-term debt. Disclosure of the fair value of pension plan assets is only required annually. Also, this rule clarifies the definition of fair value for financial reporting, establishes a framework for measuring fair value and requires additional disclosures about the use of fair value measurements. Various inputs are considered when determining the value of the Company's investments, pension plan assets and long-term debt. The inputs or methodologies used for valuing securities are not necessarily an indication of the risk associated with investing in these securities. These inputs are summarized in the three broad levels listed below. • Level 1 - observable market inputs that are unadjusted quoted prices for identical assets or liabilities in active markets; • Level 2 - other significant observable inputs (including quoted prices for similar securities, interest rates, credit risk, etc.); and • Level 3 - significant unobservable inputs (including the Company's own assumptions about the assumptions market participants would use in determining the fair value of investments). NOTE 9. Fair Value Measurements, continued The valuation methods described below may produce a fair value calculation that may not be indicative of net realizable value or reflective of future fair values. Furthermore, while the Company believes its valuation methods are appropriate and consistent with other market participants, the use of different methodologies or assumptions to determine the fair value of certain financial instruments could result in a different fair value measurement at the reporting date. Investments The Company's investment assets, valued with assistance from a third-party trustee, consist of certificates of deposits, commercial paper, corporate bonds and government securities and are carried at fair value on the consolidated balance sheet per the Fair Value Measurements and Disclosures Topic in the ASC. There are several valuation methodologies used for those assets as described below. • Certificates of Deposit and Commercial Paper (Level 2) : Valued at amortized cost, which approximates fair value; and • Corporate Bonds and Government Securities (Level 2) : Valued using broker quotes that utilize observable market inputs. The Company's investment assets are carried at fair value on the consolidated balance sheets as summarized in the following table. All of the inputs used to determine the fair value of the Company's investments are Level 2 inputs. The amortized cost basis of these investments was $705 million and $95 million as of September 30, 2018 and December 31, 2017 , respectively. (Dollars in Millions) September 30, December 31, Certificates of Deposit and Commercial Paper $ 610 $ — Corporate Bonds 56 61 Government Securities 40 34 Total investments at fair value $ 706 $ 95 These investments have the following maturities: (Dollars in millions) September 30, December 31, Less than 1 year $ 615 $ 18 1 - 5 years 17 11 5 - 10 years 25 26 Greater than 10 years 49 40 Total investments at fair value $ 706 $ 95 NOTE 9. Fair Value Measurements, continued Long-term Debt Long-term debt is reported at carrying amount on the consolidated balance sheets and is the Company's only financial instrument with fair values significantly different from their carrying amounts. The majority of the Company's long-term debt is valued with assistance from an independent third party adviser that utilizes closing transactions, market quotes or market values of comparable debt. For those instruments not valued by the independent adviser, the fair value has been estimated by applying market rates of similar instruments to the scheduled contractual debt payments and maturities. These market rates are provided by the same independent adviser. All of the inputs used to determine the fair value of the Company's long-term debt are Level 2 inputs. The fair value of outstanding debt fluctuates with changes in a number of factors. Such factors include, but are not limited to, interest rates, market conditions, credit ratings, values of similar financial instruments, size of the transaction, cash flow projections and comparable trades. Fair value will exceed carrying value when the current market interest rate is lower than the interest rate at which the debt was originally issued. The fair value of a company's debt is a measure of its current value under present market conditions. It does not impact the financial statements under current accounting rules. The fair value and carrying value of the Company's long-term debt is as follows: (Dollars in millions) September 30, December 31, Long-term Debt (Including Current Maturities): Fair Value $ 14,173 $ 13,220 Carrying Value 13,772 11,809

Other Comprehensive Income (Los

Other Comprehensive Income (Loss)	9 Months Ended
	Sep. 30, 2018
Equity [Abstract]
Other Comprehensive Income (Loss)	Other Comprehensive Income (Loss) CSX reports comprehensive earnings or loss in accordance with the Comprehensive Income Topic in the ASC in the Consolidated Comprehensive Income Statement. Total comprehensive earnings are defined as all changes in shareholders' equity during a period, other than those resulting from investments by and distributions to shareholders (e.g. issuance of equity securities and dividends). Generally, for CSX, total comprehensive earnings equal net earnings plus or minus adjustments for pension and other post-retirement liabilities. Total comprehensive earnings represent the activity for a period net of tax and were $901 million and $467 million for third quarters and $2.4 billion and $1.4 billion for nine months 2018 and 2017 , respectively. While total comprehensive earnings is the activity in a period and is largely driven by net earnings in that period, accumulated other comprehensive income or loss (“AOCI”) represents the cumulative balance of other comprehensive income, net of tax, as of the balance sheet date. For CSX, AOCI is primarily the cumulative balance related to pension and other post-retirement benefit adjustments and CSX's share of AOCI of equity method investees. Changes in the AOCI balance by component are shown in the table below. Amounts reclassified in pension and other post-employment benefits to net earnings relate to the amortization of actuarial losses and are included in other income - net on the consolidated income statements. See Note 6, Employee Benefit Plans, for further information. Other primarily represents CSX's share of AOCI of equity method investees. Amounts reclassified in other to net earnings are included in equity earnings of affiliates on the consolidated income statements. Pension and Other Post-Employment Benefits Other Accumulated Other Comprehensive Income (Loss) (Dollars in millions) Balance December 31, 2017, Net of Tax $ (440 ) $ (46 ) $ (486 ) Other Comprehensive Income (Loss) Loss Before Reclassifications — (2 ) (2 ) Amounts Reclassified to Net Earnings 31 (4 ) 27 Tax (Expense) Benefit (7 ) 1 (6 ) Reclassification of Stranded Tax Effects (108 ) 1 (107 ) Total Other Comprehensive Loss (84 ) (4 ) (88 ) Balance September 30, 2018, Net of Tax $ (524 ) $ (50 ) $ (574 )

Revenues

Revenues	9 Months Ended
	Sep. 30, 2018
Revenue from Contract with Customer [Abstract]
Revenues	Revenues The Company’s revenues are primarily derived from the transportation of freight as performance obligations that arise from its contracts with customers are satisfied. The following table presents the Company’s revenues disaggregated by lines of business as they best depict how the nature, amount, timing and uncertainty of revenue and cash flows are affected by economic factors: Third Quarters Nine Months (Dollars in millions) 2018 2017 2018 2017 Chemicals $ 596 $ 546 $ 1,741 $ 1,664 Agricultural and Food Products 325 288 959 941 Automotive 300 269 934 892 Forest Products 223 181 633 567 Metals and Equipment 205 178 589 546 Minerals 137 120 388 362 Fertilizers 104 106 332 353 Total Merchandise 1,890 1,688 5,576 5,325 Domestic Coal 347 350 937 1,029 Export Coal 241 164 723 537 Total Coal 588 514 1,660 1,566 Domestic Intermodal 331 297 948 896 International Intermodal 169 149 491 432 Total Intermodal 500 446 1,439 1,328 Other 151 95 432 326 Total $ 3,129 $ 2,743 $ 9,107 $ 8,545 Revenue Recognition The Company generates revenue from freight billings under contracts with customers generally on a rate per carload, container or ton-basis based on origin to destination and commodities carried. The Company’s performance obligation arises when it receives a bill of lading (“BOL”) to transport a customer's commodities at a negotiated price contained in a transportation services agreement or a publicly disclosed tariff rate. Once a BOL is received, a contract is formed whereby the parties are committed to perform, collectability of consideration is probable and the rights of the parties, shipping terms and conditions, and payment terms are identified. A customer may submit several BOLs for transportation services at various times throughout a service agreement term but each shipment represents a distinct service that is a separately identified performance obligation. The average transit time to complete a shipment is between 3 to 8 days and payments for transportation services are normally billed once a BOL is received and are generally due within 15 days after the invoice date. The Company recognizes revenue over transit time of freight as it moves from origin to destination. Revenue for services started but not completed at the reporting date is allocated based on the relative transit time in each reporting period, with the portion allocated for services subsequent to the reporting date considered remaining performance obligations. NOTE 11. Revenues, continued The certain key estimates included in the recognition and measurement of revenue and related accounts receivable are as follows: • Revenue associated with shipments in transit is recognized ratably over transit time and is based on average cycle times to move commodities and products from their origin to their final destination or interchange; • Adjustments to revenue for billing corrections and billing discounts; • Adjustments to revenue for overcharge claims filed by customers, which are based on historical payments to customers for rate overcharges as a percentage of total billing; • Incentive-based refunds to customers, which are primarily volume-related, are recorded as a reduction to revenue on the basis of the projected liability (this estimate is based on historical activity, current volume levels and forecasted future volume). Revenue related to interline transportation services that involve the services of another party, such as another railroad, is reported on a net basis. The portion of the gross amount billed to customers that is remitted by the Company to another party is not reflected as revenue. Other revenue, which includes revenue from regional subsidiary railroads, demurrage, switching and other incidental charges , is recorded upon completion of the service and accounted for 5% of the Company’s total revenue in the third quarter and for the nine months ended September 30, 2018. Revenue from regional subsidiary railroads includes shipments by railroads that the Company does not directly operate. Demurrage represents charges assessed when freight cars are held by a customer beyond a specified period of time. Switching revenue is primarily generated when the Company switches cars for a customer or another railroad. During the third quarters of 2018 and 2017, revenue recognized from performance obligations related to prior periods (for example, due to changes in transaction price), was not material. Remaining Performance Obligations Remaining performance obligations represent the transaction price allocated to future reporting periods for freight services started but not completed at the reporting date . This includes the unearned portion of billed and unbilled amounts for cancellable freight shipments in transit. The Company expects to recognize the unearned portion of revenue for freight services in transit within one week of the reporting date. As of September 30, 2018, the Company had no material remaining performance obligations. Contract Balances and Accounts Receivable The timing of revenue recognition, billings and cash collections results in accounts receivable and customer advances and deposits (contract liabilities) on the consolidated balance sheets. The Company had no material contract assets, contract liabilities or deferred contract costs recorded on the consolidated balance sheet as of September 30, 2018. NOTE 11. Revenues, continued The Company’s accounts receivable - net consists of freight and non-freight receivables, reduced by an allowance for doubtful accounts. (Dollars in millions) September 30, December 31, Freight Receivables $ 887 $ 810 Freight Allowance for Doubtful Accounts (17 ) (17 ) Freight Receivables, net 870 793 Non-Freight Receivables 230 186 Non-Freight Allowance for Doubtful Accounts (10 ) (9 ) Non-Freight Receivables, net 220 177 Total Accounts Receivable, net $ 1,090 $ 970 Freight receivables include amounts earned, billed and unbilled , and currently due from customers for transportation-related services. Non-freight receivables include amounts billed and unbilled and currently due related to government reimbursement receivables and other non-revenue receivables. The Company maintains an allowance for doubtful accounts to provide for the estimated amount of receivables that will not be collected. The allowance is based upon an assessment of customer creditworthiness, historical payment experience, the age of outstanding receivables and economic conditions. Impairment losses recognized on the Company’s accounts receivable were not material in the third quarters of 2018 and 2017.

Summarized Consolidating Financ

Summarized Consolidating Financial Data	9 Months Ended
	Sep. 30, 2018
Condensed Financial Information Disclosure [Abstract]
Summarized Consolidating Financial Data	Summarized Consolidating Financial Data In 2007, CSXT, a wholly-owned subsidiary of CSX Corporation, sold secured equipment notes maturing in 2023 in a registered public offering. CSX has fully and unconditionally guaranteed the notes. In connection with the notes, the Company is providing the following condensed consolidating financial information in accordance with SEC disclosure requirements. Each entity in the consolidating financial information follows the same accounting policies as described in the consolidated financial statements, except for the use of the equity method of accounting to reflect ownership interests in subsidiaries which are eliminated upon consolidation and the allocation of certain expenses of CSX incurred for the benefit of its subsidiaries. Condensed consolidating financial information for the obligor, CSXT, and parent guarantor, CSX, is shown in the following tables. Consolidating Income Statements (Dollars in millions) Third Quarter 2018 CSX Corporation CSX Transportation Eliminations and Other Consolidated Revenue $ — $ 3,110 $ 19 $ 3,129 Expense (86 ) 1,952 (30 ) 1,836 Operating Income 86 1,158 49 1,293 Equity in Earnings of Subsidiaries 953 — (953 ) — Interest (Expense) / Benefit (190 ) (11 ) 39 (162 ) Other Income / (Expense) - Net 6 35 (22 ) 19 Earnings Before Income Taxes 855 1,182 (887 ) 1,150 Income Tax Benefit / (Expense) 39 (278 ) (17 ) (256 ) Net Earnings $ 894 $ 904 $ (904 ) $ 894 Total Comprehensive Earnings $ 901 $ 903 $ (903 ) $ 901 Third Quarter 2017 CSX Corporation CSX Transportation Eliminations and Other Consolidated Revenue $ — $ 2,725 $ 18 $ 2,743 Expense (129 ) 2,031 (27 ) 1,875 Operating Income 129 694 45 868 Equity in Earnings of Subsidiaries 472 — (472 ) — Interest (Expense) / Benefit (147 ) (3 ) 18 (132 ) Other Income / (Expense) - Net 1 19 (6 ) 14 Earnings Before Income Taxes 455 710 (415 ) 750 Income Tax Benefit / (Expense) 4 (277 ) (18 ) (291 ) Net Earnings $ 459 $ 433 $ (433 ) $ 459 Total Comprehensive Earnings $ 467 $ 433 $ (433 ) $ 467 Summarized Consolidating Financial Data, continued Consolidating Income Statements (Dollars in millions) Nine Months 2018 CSX Corporation CSX Transportation Eliminations and Other Consolidated Revenue $ — $ 9,050 $ 57 $ 9,107 Expense (248 ) 5,843 (108 ) 5,487 Operating Income 248 3,207 165 3,620 Equity in Earnings of Subsidiaries 2,653 — (2,653 ) — Interest (Expense) / Benefit (535 ) (28 ) 95 (468 ) Other Income / (Expense) - Net 16 87 (49 ) 54 Earnings Before Income Taxes 2,382 3,266 (2,442 ) 3,206 Income Tax (Expense) / Benefit 84 (776 ) (48 ) (740 ) Net Earnings $ 2,466 $ 2,490 $ (2,490 ) $ 2,466 Total Comprehensive Earnings $ 2,378 $ 2,484 $ (2,484 ) $ 2,378 Nine Months 2017 CSX Corporation CSX Transportation Eliminations and Other Consolidated Revenue $ — $ 8,490 $ 55 $ 8,545 Expense (171 ) 6,225 (103 ) 5,951 Operating Income 171 2,265 158 2,594 Equity in Earnings of Subsidiaries 1,506 — (1,506 ) — Interest (Expense) / Benefit (432 ) (21 ) 47 (406 ) Other Income / (Expense) - Net 6 (21 ) (14 ) (29 ) Earnings Before Income Taxes 1,251 2,223 (1,315 ) 2,159 Income Tax (Expense) / Benefit 80 (844 ) (64 ) (828 ) Net Earnings $ 1,331 $ 1,379 $ (1,379 ) $ 1,331 Total Comprehensive Earnings $ 1,410 $ 1,378 $ (1,378 ) $ 1,410 Summarized Consolidating Financial Data, continued Consolidating Balance Sheet (Dollars in millions) September 30, 2018 CSX Corporation CSX Transportation Eliminations and Other Consolidated ASSETS Current Assets Cash and Cash Equivalents $ 537 $ 116 $ 10 $ 663 Short-term Investments 610 — 5 615 Accounts Receivable - Net 1 221 868 1,090 Receivable from Affiliates 960 5,256 (6,216 ) — Materials and Supplies — 283 — 283 Other Current Assets — 115 18 133 Total Current Assets 2,108 5,991 (5,315 ) 2,784 Properties 1 41,629 2,855 44,485 Accumulated Depreciation (1 ) (11,043 ) (1,570 ) (12,614 ) Properties - Net — 30,586 1,285 31,871 Investments in Conrail — — 941 941 Affiliates and Other Companies (39 ) 846 16 823 Investments in Consolidated Subsidiaries 31,288 — (31,288 ) — Other Long-term Assets 77 613 (248 ) 442 Total Assets $ 33,434 $ 38,036 $ (34,609 ) $ 36,861 LIABILITIES AND SHAREHOLDERS' EQUITY Current Liabilities Accounts Payable $ 189 $ 753 $ 40 $ 982 Labor and Fringe Benefits Payable 40 434 43 517 Payable to Affiliates 6,339 397 (6,736 ) — Casualty, Environmental and Other Reserves — 97 13 110 Current Maturities of Long-term Debt — 18 — 18 Income and Other Taxes Payable (415 ) 542 39 166 Other Current Liabilities 1 148 2 151 Total Current Liabilities 6,154 2,389 (6,599 ) 1,944 Casualty, Environmental and Other Reserves — 191 40 231 Long-term Debt 13,043 711 — 13,754 Deferred Income Taxes - Net (99 ) 6,484 199 6,584 Other Long-term Liabilities 617 300 (304 ) 613 Total Liabilities $ 19,715 $ 10,075 $ (6,664 ) $ 23,126 Shareholders' Equity Common Stock, $1 Par Value $ 844 $ 181 $ (181 ) $ 844 Other Capital 129 5,096 (5,096 ) 129 Retained Earnings 13,320 22,679 (22,679 ) 13,320 Accumulated Other Comprehensive Loss (574 ) (11 ) 11 (574 ) Noncontrolling Interest — 16 — 16 Total Shareholders' Equity $ 13,719 $ 27,961 $ (27,945 ) $ 13,735 Total Liabilities and Shareholders' Equity $ 33,434 $ 38,036 $ (34,609 ) $ 36,861 Summarized Consolidating Financial Data, continued Consolidating Balance Sheet (Dollars in millions) December 31, 2017 CSX Corporation CSX Transportation Eliminations and Other Consolidated ASSETS Current Assets Cash and Cash Equivalents $ 274 $ 121 $ 6 $ 401 Short-term Investments — — 18 18 Accounts Receivable - Net (1 ) 301 670 970 Receivable from Affiliates 1,226 3,517 (4,743 ) — Materials and Supplies — 372 — 372 Other Current Assets (1 ) 145 10 154 Total Current Assets 1,498 4,456 (4,039 ) 1,915 Properties 1 41,479 2,844 44,324 Accumulated Depreciation (1 ) (11,017 ) (1,542 ) (12,560 ) Properties - Net — 30,462 1,302 31,764 Investments in Conrail — — 907 907 Affiliates and Other Companies (39 ) 800 18 779 Investment in Consolidated Subsidiaries 29,405 — (29,405 ) — Other Long-term Assets 39 596 (261 ) 374 Total Assets $ 30,903 $ 36,314 $ (31,478 ) $ 35,739 LIABILITIES AND SHAREHOLDERS' EQUITY Current Liabilities Accounts Payable $ 105 $ 708 $ 34 $ 847 Labor and Fringe Benefits Payable 52 494 56 602 Payable to Affiliates 4,792 552 (5,344 ) — Casualty, Environmental and Other Reserves — 95 13 108 Current Maturities of Long-term Debt — 19 — 19 Income and Other Taxes Payable (326 ) 455 28 157 Other Current Liabilities 5 153 3 161 Total Current Liabilities 4,628 2,476 (5,210 ) 1,894 Casualty, Environmental and Other Reserves — 222 44 266 Long-term Debt 11,056 733 1 11,790 Deferred Income Taxes - Net (130 ) 6,342 206 6,418 Other Long-term Liabilities 644 320 (314 ) 650 Total Liabilities $ 16,198 $ 10,093 $ (5,273 ) $ 21,018 Shareholders' Equity Common Stock, $1 Par Value $ 890 $ 181 $ (181 ) $ 890 Other Capital 217 5,096 (5,096 ) 217 Retained Earnings 14,084 20,933 (20,933 ) 14,084 Accumulated Other Comprehensive Loss (486 ) (5 ) 5 (486 ) Noncontrolling Minority Interest — 16 — 16 Total Shareholders' Equity $ 14,705 $ 26,221 $ (26,205 ) $ 14,721 Total Liabilities and Shareholders' Equity $ 30,903 $ 36,314 $ (31,478 ) $ 35,739 Summarized Consolidating Financial Data, continued Consolidating Cash Flow Statements (Dollars in millions) Nine Months 2018 CSX Corporation CSX Transportation Eliminations and Other Consolidated Operating Activities Net Cash Provided by (Used in) Operating Activities $ 2,417 $ 1,792 $ (803 ) $ 3,406 Investing Activities Property Additions — (1,134 ) (106 ) (1,240 ) Proceeds from Property Dispositions — 257 — 257 Purchases of Short-term Investments (609 ) — (2 ) (611 ) Proceeds from Sales of Short-term Investments — — 15 15 Other Investing Activities (1 ) (149 ) 142 (8 ) Net Cash Provided by (Used in) Investing Activities (610 ) (1,026 ) 49 (1,587 ) Financing Activities Long-term Debt Issued 2,000 — — 2,000 Long-term Debt Repaid — (19 ) — (19 ) Dividends Paid (570 ) (750 ) 750 (570 ) Shares Repurchased (2,816 ) — — (2,816 ) Accelerated Share Repurchase Pending Final Settlement (100 ) — — (100 ) Other Financing Activities (58 ) (2 ) 8 (52 ) Net Cash Provided by (Used in) Financing Activities (1,544 ) (771 ) 758 (1,557 ) Net Increase (Decrease) in Cash and Cash Equivalents 263 (5 ) 4 262 Cash and Cash Equivalents at Beginning of Period 274 121 6 401 Cash and Cash Equivalents at End of Period $ 537 $ 116 $ 10 $ 663 NOTE 12. Summarized Consolidating Financial Data, continued Consolidating Cash Flow Statements (Dollars in millions) Nine Months 2017 CSX Corporation CSX Transportation Eliminations and Other Consolidated Operating Activities Net Cash Provided by (Used in) Operating Activities $ 1,590 $ 1,544 $ (273 ) $ 2,861 Investing Activities Property Additions — (1,311 ) (151 ) (1,462 ) Proceeds from Property Dispositions — 38 — 38 Purchases of Short-term Investments (639 ) — (6 ) (645 ) Proceeds from Sales of Short-term Investments 955 — 2 957 Other Investing Activities (2 ) 60 (25 ) 33 Net Cash Provided by (Used in) Investing Activities 314 (1,213 ) (180 ) (1,079 ) Financing Activities Long-term Debt Issued 850 — — 850 Long-term Debt Repaid (312 ) (20 ) — (332 ) Dividends Paid (530 ) (450 ) 450 (530 ) Shares Repurchased (1,763 ) — — (1,763 ) Other Financing Activities (21 ) 5 (3 ) (19 ) Net Cash Provided by (Used in) Financing Activities (1,776 ) (465 ) 447 (1,794 ) Net Increase (Decrease) in Cash and Cash Equivalents 128 (134 ) (6 ) (12 ) Cash and Cash Equivalents at Beginning of Period 305 281 17 603 Cash and Cash Equivalents at End of Period $ 433 $ 147 $ 11 $ 591

Nature of Operations and Sign_2

Nature of Operations and Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	In the opinion of management, the accompanying consolidated financial statements contain all normal, recurring adjustments necessary to fairly present the following: • Consolidated income statements for the quarter and nine months ended September 30, 2018 and September 30, 2017 ; • Condensed consolidated comprehensive income statements for the quarter and nine months ended September 30, 2018 and September 30, 2017 ; • Consolidated balance sheets at September 30, 2018 and December 31, 2017 ; and • Consolidated cash flow statements for the nine months ended September 30, 2018 and September 30, 2017 . NOTE 1. Nature of Operations and Significant Accounting Policies, continued Pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”), certain information and disclosures normally included in the notes to the annual financial statements prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) have been omitted from these interim financial statements. CSX suggests that these financial statements be read in conjunction with the audited financial statements and the notes included in CSX's most recent annual report on Form 10-K and any subsequently filed current reports on Form 8-K.
Fiscal Year	Through the second quarter 2017, CSX followed a 52/53 week fiscal reporting calendar with the last day of each reporting period ending on a Friday. On July 7, 2017 the Board of Directors of CSX approved a change in the fiscal reporting calendar from a 52/53 week year ending on the last Friday of December to a calendar year ending on December 31 each year, effective beginning with fiscal third quarter 2017. Related to the change in the fiscal calendar: • Fiscal year 2018 (January 1, 2018 through December 31, 2018) will contain 365 days, and fiscal year 2017 (December 31, 2016 through December 31, 2017) contained 366 days. • Fiscal first quarter 2018 (January 1, 2018 through March 31, 2018) contained 90 days, and fiscal first quarter 2017 (December 31, 2016 through March 31, 2017) contained 91 days. • Fiscal second quarter 2018 (April 1, 2018 through June 30, 2018) contained 91 days, and fiscal second quarter 2017 (April 1, 2017 through June 30, 2017) contained 91 days. • Fiscal third quarter 2018 (July 1, 2018 through September 30, 2018) contained 92 days, and fiscal third quarter 2017 (July 1, 2017 through September 30, 2017) contained 92 days. This change did not materially impact the comparability of the Company’s financial results. Accordingly, the change to a calendar fiscal year was made on a prospective basis and operating results for prior periods were not adjusted. The Company was not required to file a transition report because this change was not deemed a change in fiscal year for purposes of reporting subject to Rule 13a-10 or Rule 15d-10 of the Securities Exchange Act of 1934 as the new fiscal year commenced with the end of the prior fiscal year end and within seven days of the prior fiscal year end. Except as otherwise specified, references to “ third quarter(s)” or “ nine months” indicate CSX's fiscal periods ending September 30, 2018 and September 30, 2017 , and references to "year-end" indicate the fiscal year ended December 31, 2017 .
New Accounting Pronouncements	In February 2018, the Financial Accounting Standards Board ("FASB") issued Accounting Standard Update ("ASU") Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Inco me, which permits entities to reclassify tax effects stranded in accumulated other comprehensive income as a result of tax reform to retained earnings. Companies that elect to reclassify these amounts must reclassify stranded tax effects for all items accounted for in accumulated other comprehensive income. The Company adopted this standard update in first quarter 2018 and applied it prospectively. Adoption resulted in the reclassification of $107 million in tax effects related to employee benefit plans from accumulated other comprehensive loss, increasing retained earnings by the same amount. NOTE 1. Nature of Operations and Significant Accounting Policies, continued In March 2017, the FASB issued ASU Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost , which requires that only the service cost component of net periodic benefit costs be recorded as compensation cost in operating expense on the consolidated income statement. All other components of net periodic benefit cost (interest cost, expected return on plan assets, amortization of net loss, special termination benefits and settlement and curtailment effects) should be presented as non-operating charges on the consolidated income statement. If these non-operating charges are related to prior year restructuring activities, they are presented as restructuring charge - non-operating. Other non-operating charges are presented as other income - net. The Company adopted the provisions of this standard during first quarter 2018 and applied them retrospectively. The retrospective impact of adoption for third quarter and nine months 2017 is shown in the following table. Third Quarter 2017 Nine Months 2017 (Dollars in millions) As Previously Reported Reclass As Reclassified As Previously Reported Reclass As Reclassified Operating Expense: Labor and Fringe $ 717 $ 8 $ 725 $ 2,249 $ 22 $ 2,271 Restructuring Charge 1 — 1 296 (70 ) 226 Non-Operating Income (Expense): Restructuring Charge - Non-Operating $ — $ — $ — $ — $ (70 ) $ (70 ) Other Income - Net 6 8 14 19 22 41 In May 2014, the FASB issued ASU Revenue from Contracts with Customers , which supersedes previous revenue recognition guidance. The new standard requires that a company recognize revenue when it transfers promised goods or services to customers in an amount that reflects the consideration the company expects to receive in exchange for those goods or services. In-depth reviews of commercial contracts were completed and changes to processes and internal controls to meet the standard’s reporting and disclosure requirements were implemented. The Company adopted the guidance effective January 1, 2018 using the modified retrospective approach. The adoption did not affect the Company’s financial condition, results of operations or liquidity. Disclosures related to the nature, amount and timing of revenue and cash flows arising from contracts with customers are included in Note 11, Revenues. Pronouncements to be adopted In February 2016, the FASB issued ASU, Leases , which will require lessees to recognize most leases on their balance sheets as a right-of-use asset with a corresponding lease liability, and lessors to recognize a net lease investment. Additional qualitative and quantitative disclosures will also be required. This standard update is effective for CSX beginning with the first quarter 2019 and the Company plans to adopt it using the cumulative-effect adjustment transition method approved by the FASB in July 2018. Changes to processes and internal controls to meet the standard’s reporting and disclosure requirements have been identified and are being implemented. Software has been implemented that will assist in the recognition of additional assets and liabilities to be included on the balance sheet related to leases currently classified as operating leases with durations greater than twelve months, with certain allowable exceptions. In addition to lease agreements, service contracts and other agreements are also being reviewed to determine if they contain an embedded lease. The Company continues to evaluate the expected impact of this standard update on disclosures, but does not anticipate any material changes to operating results or liquidity as a result of right-of-use assets and corresponding lease liabilities that will be recorded. NOTE 1. Nature of Operations and Significant Accounting Policies, continued In January 2018, the FASB issued ASU Leases - Land Easement Practical Expedient , which permits entities to forgo the evaluation of existing land easement arrangements to determine if they contain a lease as part of the adoption of the Leases ASU issued in February 2016. Accordingly, the Company’s accounting treatment of existing land easements will not change. CSX will adopt this standard update concurrently with the Leases ASU issued in February 2016. New land easement arrangements, or modifications to existing arrangements, after the adoption of the standard update will still be evaluated to determine if they meet the definition of a lease. In March 2017, the FASB issued ASU Simplifying the Test for Goodwill Impairment, which eliminates step two, the calculation of the implied fair value of goodwill, from the goodwill impairment test. Impairment will be quantified in step one of the test as the amount by which the carrying amount exceeds the fair value. This standard update is effective beginning first quarter 2020 and must be applied prospectively. The Company does not believe this standard update will have a material effect on its financial condition, results of operations or liquidity.

Nature of Operations and Sign_3

Nature of Operations and Significant Accounting Policies (Tables)	9 Months Ended
	Sep. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of Retrospective Impact of Adoption	The retrospective impact of adoption for third quarter and nine months 2017 is shown in the following table. Third Quarter 2017 Nine Months 2017 (Dollars in millions) As Previously Reported Reclass As Reclassified As Previously Reported Reclass As Reclassified Operating Expense: Labor and Fringe $ 717 $ 8 $ 725 $ 2,249 $ 22 $ 2,271 Restructuring Charge 1 — 1 296 (70 ) 226 Non-Operating Income (Expense): Restructuring Charge - Non-Operating $ — $ — $ — $ — $ (70 ) $ (70 ) Other Income - Net 6 8 14 19 22 41
Restructuring Charges	Expenses related to the management workforce reduction and other costs during the nine months 2017 are shown in the following table. Nine Months 2017 (Dollars in millions) As Previously Reported Operating Restructuring Charge Non-Operating Restructuring Charge Severance and Pension $ 144 $ 91 $ 53 Other Post-Retirement Benefits Curtailment 17 — 17 Employee Equity Awards Proration and Other 16 16 — Subtotal Management Workforce Reduction $ 177 $ 107 $ 70 Reimbursement Arrangements 84 84 — Executive Equity Awards Proration 24 24 — Advisory Fees Related to Shareholder Matters 11 11 — Total Restructuring Charge $ 296 $ 226 $ 70

Earnings Per Share (Tables)

Earnings Per Share (Tables)	9 Months Ended
	Sep. 30, 2018
Earnings Per Share [Abstract]
Computation of Basic Earnings Per Share, Assuming Dilution	The following table sets forth the computation of basic earnings per share and earnings per share, assuming dilution: Third Quarters Nine Months 2018 2017 2018 2017 Numerator (Dollars in millions) : Net Earnings $ 894 $ 459 $ 2,466 $ 1,331 Dividend Equivalents on Restricted Stock — — — (1 ) Net Earnings, Attributable to Common Shareholders $ 894 $ 459 $ 2,466 $ 1,330 Denominator (Units in millions) : Average Common Shares Outstanding 850 902 866 916 Other Potentially Dilutive Common Shares 4 4 4 3 Average Common Shares Outstanding, Assuming Dilution 854 906 870 919 Net Earnings Per Share, Basic $ 1.05 $ 0.51 $ 2.85 $ 1.45 Net Earnings Per Share, Assuming Dilution $ 1.05 $ 0.51 $ 2.83 $ 1.45

Share-Based Compensation (Table

Share-Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Share-Based Compensation and Related Income Tax Benefit	Total pre-tax expense associated with share-based compensation and its related income tax benefit is shown in the table below. The year over year decrease in third quarter share-based compensation expense is primarily due to the prior year expense related to 9 million stock options granted in February 2017 to former President and CEO E. Hunter Harrison, which were forfeited upon his death in December 2017. Additionally, the decrease in nine months expense was also due to modifications to the terms of awards in the first and second quarters of 2017 (see Equity Award Modifications below). Third Quarters Nine Months (Dollars in millions) 2018 2017 2018 2017 Share-Based Compensation Expense: Performance Units $ 8 $ 3 $ 22 $ 41 Stock Options 4 14 10 47 Restricted Stock Units and Awards 1 2 4 11 Stock Awards for Directors — — 2 2 Total Share-Based Compensation Expense $ 13 $ 19 $ 38 $ 101 Income Tax Benefit $ 6 $ 12 $ 23 $ 41
Schedule of Weighted Average Assumptions	The fair value of the performance units awarded during the quarter and nine months ended September 30, 2018 was calculated using a Monte-Carlo simulation model with the following weighted-average assumptions: Third Quarter Nine Months 2018 2018 Weighted-average assumptions used: Annual dividend yield 1.2 % 1.6 % Risk-free interest rate 2.7 % 2.3 % Annualized volatility 27.9 % 29.1 % Expected life (in years) 2.3 2.9
Summary of Fair Value Assumptions for Stock Option Awards	The fair values of all stock option awards during the quarter and nine months ended September 30, 2018 and September 30, 2017 were estimated at the grant date with the following weighted average assumptions: Third Quarters Nine Months 2018 2017 2018 2017 Weighted-average grant date fair value $ 20.52 $ — $ 14.65 $ 12.83 Stock options valuation assumptions: Annual dividend yield 1.2 % — % 1.5 % 1.5 % Risk-free interest rate 2.8 % — % 2.6 % 2.2 % Annualized volatility 25.5 % — % 27.0 % 27.1 % Expected life (in years) 6.5 — 6.5 6.3 Other pricing model inputs: Weighted-average grant-date market price of CSX stock (strike price) $ 74.84 $ — $ 54.19 $ 49.60

Casualty, Environmental and O_2

Casualty, Environmental and Other Reserves (Tables)	9 Months Ended
	Sep. 30, 2018
Casualty, Environmental and Other Reserves [Abstract]
Schedule of Casualty, Environmental and Other Reserves	Personal injury and environmental reserves are considered critical accounting estimates due to the need for significant management judgment. Casualty, environmental and other reserves are provided for in the consolidated balance sheets as shown in the table below. September 30, 2018 December 31, 2017 (Dollars in millions) Current Long-term Total Current Long-term Total Casualty: Personal Injury $ 42 $ 108 $ 150 $ 43 $ 125 $ 168 Occupational 7 47 54 6 54 60 Total Casualty 49 155 204 49 179 228 Environmental 37 52 89 31 59 90 Other 24 24 48 28 28 56 Total $ 110 $ 231 $ 341 $ 108 $ 266 $ 374

Employee Benefit Plans (Tables)

Employee Benefit Plans (Tables)	9 Months Ended
	Sep. 30, 2018
Retirement Benefits [Abstract]
Components of Expense/(Income) Related to Net Benefit Expense	Pension Benefits (Dollars in millions) Third Quarters Nine Months 2018 2017 2018 2017 Service Cost Included in Labor and Fringe $ 8 $ 8 $ 24 $ 28 Interest Cost 23 23 69 69 Expected Return on Plan Assets (44 ) (43 ) (131 ) (128 ) Amortization of Net Loss 10 10 30 31 Total Income Included in Other Income - Net (11 ) (10 ) (32 ) (28 ) Net Periodic Benefit Cost $ (3 ) $ (2 ) $ (8 ) $ — Restructuring Charges - Non Operating (a) — — — 57 Total (Income) Expense $ (3 ) $ (2 ) $ (8 ) $ 57 Other Post-retirement Benefits (Dollars in millions) Third Quarters Nine Months 2018 2017 2018 2017 Service Cost Included in Labor and Fringe $ — $ — $ 1 $ 1 Interest Cost 2 2 5 6 Total Expense Included in Other Income - Net 2 2 5 6 Net Periodic Benefit Cost $ 2 $ 2 $ 6 $ 7 Restructuring Charges - Non Operating (a) — — — 13 Total Expense $ 2 $ 2 $ 6 $ 20 (a) Charges related to special termination benefits and curtailment costs were the result of the management workforce reductions in first quarter 2017. See Restructuring Charge in Note 1, Nature of Operations and Significant Accounting Policies.

Debt and Credit Agreements (Tab

Debt and Credit Agreements (Tables)	9 Months Ended
	Sep. 30, 2018
Debt Disclosure [Abstract]
Activity Related to Long-Term Debt	Total activity related to long-term debt as of the end of third quarter 2018 is shown in the table below. For fair value information related to the Company's long-term debt, see Note 9, Fair Value Measurements. (Dollars in millions) Current Portion Long-term Portion Total Long-term debt as of December 31, 2017 $ 19 $ 11,790 $ 11,809 2018 activity: Long-term debt issued — 2,000 2,000 Long-term debt repaid (19 ) — (19 ) Reclassifications 18 (18 ) — Discount, premium and other activity — (18 ) (18 ) Long-term debt as of September 30, 2018 $ 18 $ 13,754 $ 13,772

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2018
Fair Value Disclosures [Abstract]
Schedule of Fair Value of Investment Assets	(Dollars in Millions) September 30, December 31, Certificates of Deposit and Commercial Paper $ 610 $ — Corporate Bonds 56 61 Government Securities 40 34 Total investments at fair value $ 706 $ 95
Schedule of Investment Maturities	These investments have the following maturities: (Dollars in millions) September 30, December 31, Less than 1 year $ 615 $ 18 1 - 5 years 17 11 5 - 10 years 25 26 Greater than 10 years 49 40 Total investments at fair value $ 706 $ 95
Schedule of Fair Value and Carrying Value of Long-Term Debt	The fair value and carrying value of the Company's long-term debt is as follows: (Dollars in millions) September 30, December 31, Long-term Debt (Including Current Maturities): Fair Value $ 14,173 $ 13,220 Carrying Value 13,772 11,809

Other Comprehensive Income (L_2

Other Comprehensive Income (Loss) (Tables)	9 Months Ended
	Sep. 30, 2018
Equity [Abstract]
Changes in AOCI balance by Component	Changes in the AOCI balance by component are shown in the table below. Amounts reclassified in pension and other post-employment benefits to net earnings relate to the amortization of actuarial losses and are included in other income - net on the consolidated income statements. See Note 6, Employee Benefit Plans, for further information. Other primarily represents CSX's share of AOCI of equity method investees. Amounts reclassified in other to net earnings are included in equity earnings of affiliates on the consolidated income statements. Pension and Other Post-Employment Benefits Other Accumulated Other Comprehensive Income (Loss) (Dollars in millions) Balance December 31, 2017, Net of Tax $ (440 ) $ (46 ) $ (486 ) Other Comprehensive Income (Loss) Loss Before Reclassifications — (2 ) (2 ) Amounts Reclassified to Net Earnings 31 (4 ) 27 Tax (Expense) Benefit (7 ) 1 (6 ) Reclassification of Stranded Tax Effects (108 ) 1 (107 ) Total Other Comprehensive Loss (84 ) (4 ) (88 ) Balance September 30, 2018, Net of Tax $ (524 ) $ (50 ) $ (574 )

Revenues (Tables)

Revenues (Tables)	9 Months Ended
	Sep. 30, 2018
Revenue from Contract with Customer [Abstract]
Schedule of Revenues Disaggregated by Lines of Business	The following table presents the Company’s revenues disaggregated by lines of business as they best depict how the nature, amount, timing and uncertainty of revenue and cash flows are affected by economic factors: Third Quarters Nine Months (Dollars in millions) 2018 2017 2018 2017 Chemicals $ 596 $ 546 $ 1,741 $ 1,664 Agricultural and Food Products 325 288 959 941 Automotive 300 269 934 892 Forest Products 223 181 633 567 Metals and Equipment 205 178 589 546 Minerals 137 120 388 362 Fertilizers 104 106 332 353 Total Merchandise 1,890 1,688 5,576 5,325 Domestic Coal 347 350 937 1,029 Export Coal 241 164 723 537 Total Coal 588 514 1,660 1,566 Domestic Intermodal 331 297 948 896 International Intermodal 169 149 491 432 Total Intermodal 500 446 1,439 1,328 Other 151 95 432 326 Total $ 3,129 $ 2,743 $ 9,107 $ 8,545
Schedule of Accounts Receivable	The Company’s accounts receivable - net consists of freight and non-freight receivables, reduced by an allowance for doubtful accounts. (Dollars in millions) September 30, December 31, Freight Receivables $ 887 $ 810 Freight Allowance for Doubtful Accounts (17 ) (17 ) Freight Receivables, net 870 793 Non-Freight Receivables 230 186 Non-Freight Allowance for Doubtful Accounts (10 ) (9 ) Non-Freight Receivables, net 220 177 Total Accounts Receivable, net $ 1,090 $ 970

Summarized Consolidating Fina_2

Summarized Consolidating Financial Data (Tables)	9 Months Ended
	Sep. 30, 2018
Condensed Financial Information Disclosure [Abstract]
Consolidating Income Statements	Consolidating Income Statements (Dollars in millions) Third Quarter 2018 CSX Corporation CSX Transportation Eliminations and Other Consolidated Revenue $ — $ 3,110 $ 19 $ 3,129 Expense (86 ) 1,952 (30 ) 1,836 Operating Income 86 1,158 49 1,293 Equity in Earnings of Subsidiaries 953 — (953 ) — Interest (Expense) / Benefit (190 ) (11 ) 39 (162 ) Other Income / (Expense) - Net 6 35 (22 ) 19 Earnings Before Income Taxes 855 1,182 (887 ) 1,150 Income Tax Benefit / (Expense) 39 (278 ) (17 ) (256 ) Net Earnings $ 894 $ 904 $ (904 ) $ 894 Total Comprehensive Earnings $ 901 $ 903 $ (903 ) $ 901 Third Quarter 2017 CSX Corporation CSX Transportation Eliminations and Other Consolidated Revenue $ — $ 2,725 $ 18 $ 2,743 Expense (129 ) 2,031 (27 ) 1,875 Operating Income 129 694 45 868 Equity in Earnings of Subsidiaries 472 — (472 ) — Interest (Expense) / Benefit (147 ) (3 ) 18 (132 ) Other Income / (Expense) - Net 1 19 (6 ) 14 Earnings Before Income Taxes 455 710 (415 ) 750 Income Tax Benefit / (Expense) 4 (277 ) (18 ) (291 ) Net Earnings $ 459 $ 433 $ (433 ) $ 459 Total Comprehensive Earnings $ 467 $ 433 $ (433 ) $ 467 Summarized Consolidating Financial Data, continued Consolidating Income Statements (Dollars in millions) Nine Months 2018 CSX Corporation CSX Transportation Eliminations and Other Consolidated Revenue $ — $ 9,050 $ 57 $ 9,107 Expense (248 ) 5,843 (108 ) 5,487 Operating Income 248 3,207 165 3,620 Equity in Earnings of Subsidiaries 2,653 — (2,653 ) — Interest (Expense) / Benefit (535 ) (28 ) 95 (468 ) Other Income / (Expense) - Net 16 87 (49 ) 54 Earnings Before Income Taxes 2,382 3,266 (2,442 ) 3,206 Income Tax (Expense) / Benefit 84 (776 ) (48 ) (740 ) Net Earnings $ 2,466 $ 2,490 $ (2,490 ) $ 2,466 Total Comprehensive Earnings $ 2,378 $ 2,484 $ (2,484 ) $ 2,378 Nine Months 2017 CSX Corporation CSX Transportation Eliminations and Other Consolidated Revenue $ — $ 8,490 $ 55 $ 8,545 Expense (171 ) 6,225 (103 ) 5,951 Operating Income 171 2,265 158 2,594 Equity in Earnings of Subsidiaries 1,506 — (1,506 ) — Interest (Expense) / Benefit (432 ) (21 ) 47 (406 ) Other Income / (Expense) - Net 6 (21 ) (14 ) (29 ) Earnings Before Income Taxes 1,251 2,223 (1,315 ) 2,159 Income Tax (Expense) / Benefit 80 (844 ) (64 ) (828 ) Net Earnings $ 1,331 $ 1,379 $ (1,379 ) $ 1,331 Total Comprehensive Earnings $ 1,410 $ 1,378 $ (1,378 ) $ 1,410
Consolidating Balance Sheet	Consolidating Balance Sheet (Dollars in millions) September 30, 2018 CSX Corporation CSX Transportation Eliminations and Other Consolidated ASSETS Current Assets Cash and Cash Equivalents $ 537 $ 116 $ 10 $ 663 Short-term Investments 610 — 5 615 Accounts Receivable - Net 1 221 868 1,090 Receivable from Affiliates 960 5,256 (6,216 ) — Materials and Supplies — 283 — 283 Other Current Assets — 115 18 133 Total Current Assets 2,108 5,991 (5,315 ) 2,784 Properties 1 41,629 2,855 44,485 Accumulated Depreciation (1 ) (11,043 ) (1,570 ) (12,614 ) Properties - Net — 30,586 1,285 31,871 Investments in Conrail — — 941 941 Affiliates and Other Companies (39 ) 846 16 823 Investments in Consolidated Subsidiaries 31,288 — (31,288 ) — Other Long-term Assets 77 613 (248 ) 442 Total Assets $ 33,434 $ 38,036 $ (34,609 ) $ 36,861 LIABILITIES AND SHAREHOLDERS' EQUITY Current Liabilities Accounts Payable $ 189 $ 753 $ 40 $ 982 Labor and Fringe Benefits Payable 40 434 43 517 Payable to Affiliates 6,339 397 (6,736 ) — Casualty, Environmental and Other Reserves — 97 13 110 Current Maturities of Long-term Debt — 18 — 18 Income and Other Taxes Payable (415 ) 542 39 166 Other Current Liabilities 1 148 2 151 Total Current Liabilities 6,154 2,389 (6,599 ) 1,944 Casualty, Environmental and Other Reserves — 191 40 231 Long-term Debt 13,043 711 — 13,754 Deferred Income Taxes - Net (99 ) 6,484 199 6,584 Other Long-term Liabilities 617 300 (304 ) 613 Total Liabilities $ 19,715 $ 10,075 $ (6,664 ) $ 23,126 Shareholders' Equity Common Stock, $1 Par Value $ 844 $ 181 $ (181 ) $ 844 Other Capital 129 5,096 (5,096 ) 129 Retained Earnings 13,320 22,679 (22,679 ) 13,320 Accumulated Other Comprehensive Loss (574 ) (11 ) 11 (574 ) Noncontrolling Interest — 16 — 16 Total Shareholders' Equity $ 13,719 $ 27,961 $ (27,945 ) $ 13,735 Total Liabilities and Shareholders' Equity $ 33,434 $ 38,036 $ (34,609 ) $ 36,861 Consolidating Balance Sheet (Dollars in millions) December 31, 2017 CSX Corporation CSX Transportation Eliminations and Other Consolidated ASSETS Current Assets Cash and Cash Equivalents $ 274 $ 121 $ 6 $ 401 Short-term Investments — — 18 18 Accounts Receivable - Net (1 ) 301 670 970 Receivable from Affiliates 1,226 3,517 (4,743 ) — Materials and Supplies — 372 — 372 Other Current Assets (1 ) 145 10 154 Total Current Assets 1,498 4,456 (4,039 ) 1,915 Properties 1 41,479 2,844 44,324 Accumulated Depreciation (1 ) (11,017 ) (1,542 ) (12,560 ) Properties - Net — 30,462 1,302 31,764 Investments in Conrail — — 907 907 Affiliates and Other Companies (39 ) 800 18 779 Investment in Consolidated Subsidiaries 29,405 — (29,405 ) — Other Long-term Assets 39 596 (261 ) 374 Total Assets $ 30,903 $ 36,314 $ (31,478 ) $ 35,739 LIABILITIES AND SHAREHOLDERS' EQUITY Current Liabilities Accounts Payable $ 105 $ 708 $ 34 $ 847 Labor and Fringe Benefits Payable 52 494 56 602 Payable to Affiliates 4,792 552 (5,344 ) — Casualty, Environmental and Other Reserves — 95 13 108 Current Maturities of Long-term Debt — 19 — 19 Income and Other Taxes Payable (326 ) 455 28 157 Other Current Liabilities 5 153 3 161 Total Current Liabilities 4,628 2,476 (5,210 ) 1,894 Casualty, Environmental and Other Reserves — 222 44 266 Long-term Debt 11,056 733 1 11,790 Deferred Income Taxes - Net (130 ) 6,342 206 6,418 Other Long-term Liabilities 644 320 (314 ) 650 Total Liabilities $ 16,198 $ 10,093 $ (5,273 ) $ 21,018 Shareholders' Equity Common Stock, $1 Par Value $ 890 $ 181 $ (181 ) $ 890 Other Capital 217 5,096 (5,096 ) 217 Retained Earnings 14,084 20,933 (20,933 ) 14,084 Accumulated Other Comprehensive Loss (486 ) (5 ) 5 (486 ) Noncontrolling Minority Interest — 16 — 16 Total Shareholders' Equity $ 14,705 $ 26,221 $ (26,205 ) $ 14,721 Total Liabilities and Shareholders' Equity $ 30,903 $ 36,314 $ (31,478 ) $ 35,739
Consolidating Cash Flow Statements	Consolidating Cash Flow Statements (Dollars in millions) Nine Months 2018 CSX Corporation CSX Transportation Eliminations and Other Consolidated Operating Activities Net Cash Provided by (Used in) Operating Activities $ 2,417 $ 1,792 $ (803 ) $ 3,406 Investing Activities Property Additions — (1,134 ) (106 ) (1,240 ) Proceeds from Property Dispositions — 257 — 257 Purchases of Short-term Investments (609 ) — (2 ) (611 ) Proceeds from Sales of Short-term Investments — — 15 15 Other Investing Activities (1 ) (149 ) 142 (8 ) Net Cash Provided by (Used in) Investing Activities (610 ) (1,026 ) 49 (1,587 ) Financing Activities Long-term Debt Issued 2,000 — — 2,000 Long-term Debt Repaid — (19 ) — (19 ) Dividends Paid (570 ) (750 ) 750 (570 ) Shares Repurchased (2,816 ) — — (2,816 ) Accelerated Share Repurchase Pending Final Settlement (100 ) — — (100 ) Other Financing Activities (58 ) (2 ) 8 (52 ) Net Cash Provided by (Used in) Financing Activities (1,544 ) (771 ) 758 (1,557 ) Net Increase (Decrease) in Cash and Cash Equivalents 263 (5 ) 4 262 Cash and Cash Equivalents at Beginning of Period 274 121 6 401 Cash and Cash Equivalents at End of Period $ 537 $ 116 $ 10 $ 663 NOTE 12. Summarized Consolidating Financial Data, continued Consolidating Cash Flow Statements (Dollars in millions) Nine Months 2017 CSX Corporation CSX Transportation Eliminations and Other Consolidated Operating Activities Net Cash Provided by (Used in) Operating Activities $ 1,590 $ 1,544 $ (273 ) $ 2,861 Investing Activities Property Additions — (1,311 ) (151 ) (1,462 ) Proceeds from Property Dispositions — 38 — 38 Purchases of Short-term Investments (639 ) — (6 ) (645 ) Proceeds from Sales of Short-term Investments 955 — 2 957 Other Investing Activities (2 ) 60 (25 ) 33 Net Cash Provided by (Used in) Investing Activities 314 (1,213 ) (180 ) (1,079 ) Financing Activities Long-term Debt Issued 850 — — 850 Long-term Debt Repaid (312 ) (20 ) — (332 ) Dividends Paid (530 ) (450 ) 450 (530 ) Shares Repurchased (1,763 ) — — (1,763 ) Other Financing Activities (21 ) 5 (3 ) (19 ) Net Cash Provided by (Used in) Financing Activities (1,776 ) (465 ) 447 (1,794 ) Net Increase (Decrease) in Cash and Cash Equivalents 128 (134 ) (6 ) (12 ) Cash and Cash Equivalents at Beginning of Period 305 281 17 603 Cash and Cash Equivalents at End of Period $ 433 $ 147 $ 11 $ 591

Nature of Operations and Sign_4

Nature of Operations and Significant Accounting Policies - Narrative (Details) mi in Thousands, $ in Millions	3 Months Ended
	Sep. 30, 2017USD ($)	Sep. 30, 2018statemi	Mar. 31, 2018USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total number of rail route miles | mi		21
Number of states rail network serves | state		23
Advisory Fees Related to Shareholder Matters
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Incurred cost	$ 1
Accumulated Other Comprehensive Income (Loss)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reclassification adjustment			$ (107)
Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reclassification adjustment			$ 107

Nature of Operations and Sign_5

Nature of Operations and Significant Accounting Policies - Schedule of Retrospective Impact of Adoption (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Labor and Fringe	$ 695	$ 725	$ 2,060	$ 2,271
Restructuring Charge	0	1	0	226
Restructuring Charge - Non-Operating	0	0	0	(70)
Other Income - Net	$ 19	14	$ 54	41
As Previously Reported
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Labor and Fringe		717		2,249
Restructuring Charge		1		296
Restructuring Charge - Non-Operating		0		0
Other Income - Net		6		19
Reclass
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Labor and Fringe		8		22
Restructuring Charge		0		(70)
Restructuring Charge - Non-Operating		0		(70)
Other Income - Net		$ 8		$ 22

Nature of Operations and Sign_6

Nature of Operations and Significant Accounting Policies - Restructuring Charges (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Restructuring Cost and Reserve [Line Items]
Restructuring Charge	$ 0	$ 1	$ 0	$ 226
Restructuring Charges Nonoperating	$ 0	0	$ 0	70
Management Streamlining Initiative
Restructuring Cost and Reserve [Line Items]
Restructuring Charge				226
Restructuring Charges Nonoperating				70
Management Streamlining Initiative | Subtotal Management Workforce Reduction
Restructuring Cost and Reserve [Line Items]
Restructuring Charge				107
Restructuring Charges Nonoperating				70
Management Streamlining Initiative | Severance and Pension
Restructuring Cost and Reserve [Line Items]
Restructuring Charge				91
Restructuring Charges Nonoperating				53
Management Streamlining Initiative | Other Post-Retirement Benefits Curtailment
Restructuring Cost and Reserve [Line Items]
Restructuring Charge				0
Restructuring Charges Nonoperating				17
Management Streamlining Initiative | Employee Equity Awards Proration and Other
Restructuring Cost and Reserve [Line Items]
Restructuring Charge				16
Restructuring Charges Nonoperating				0
Management Streamlining Initiative | Reimbursement Arrangements
Restructuring Cost and Reserve [Line Items]
Restructuring Charge				84
Restructuring Charges Nonoperating				0
Management Streamlining Initiative | Executive Equity Awards Proration
Restructuring Cost and Reserve [Line Items]
Restructuring Charge				24
Restructuring Charges Nonoperating				0
Management Streamlining Initiative | Advisory Fees Related to Shareholder Matters
Restructuring Cost and Reserve [Line Items]
Restructuring Charge				11
Restructuring Charges Nonoperating				0
As Previously Reported
Restructuring Cost and Reserve [Line Items]
Restructuring Charge		1		296
Restructuring Charges Nonoperating		$ 0		0
As Previously Reported | Management Streamlining Initiative
Restructuring Cost and Reserve [Line Items]
Restructuring Charge				296
As Previously Reported | Management Streamlining Initiative | Subtotal Management Workforce Reduction
Restructuring Cost and Reserve [Line Items]
Restructuring Charge				177
As Previously Reported | Management Streamlining Initiative | Severance and Pension
Restructuring Cost and Reserve [Line Items]
Restructuring Charge				144
As Previously Reported | Management Streamlining Initiative | Other Post-Retirement Benefits Curtailment
Restructuring Cost and Reserve [Line Items]
Restructuring Charge				17
As Previously Reported | Management Streamlining Initiative | Employee Equity Awards Proration and Other
Restructuring Cost and Reserve [Line Items]
Restructuring Charge				16
As Previously Reported | Management Streamlining Initiative | Reimbursement Arrangements
Restructuring Cost and Reserve [Line Items]
Restructuring Charge				84
As Previously Reported | Management Streamlining Initiative | Executive Equity Awards Proration
Restructuring Cost and Reserve [Line Items]
Restructuring Charge				24
As Previously Reported | Management Streamlining Initiative | Advisory Fees Related to Shareholder Matters
Restructuring Cost and Reserve [Line Items]
Restructuring Charge				$ 11

Earnings Per Share - Computatio

Earnings Per Share - Computation of Basic Earnings Per Share, Assuming Dilution (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Numerator:
Net Earnings	$ 894	$ 459	$ 2,466	$ 1,331
Dividend Equivalents on Restricted Stock	0	0	0	(1)
Net Earnings, Attributable to Common Shareholders	$ 894	$ 459	$ 2,466	$ 1,330
Denominator:
Average Common Shares Outstanding (in shares)	850	902	866	916
Other Potentially Dilutive Common Shares (in shares)	4	4	4	3
Average Common Shares Outstanding, Assuming Dilution (in shares)	854	906	870	919
Net Earnings Per Share, Basic (in dollars per share)	$ 1.05	$ 0.51	$ 2.85	$ 1.45
Net Earnings Per Share, Assuming Dilution (in dollars per share)	$ 1.05	$ 0.51	$ 2.83	$ 1.45

Earnings Per Share - Narrative

Earnings Per Share - Narrative (Details) - USD ($) shares in Thousands	1 Months Ended	3 Months Ended			4 Months Ended	9 Months Ended
	Feb. 28, 2018	Oct. 10, 2018	Sep. 30, 2018	Sep. 30, 2017	Jul. 31, 2018	Sep. 30, 2018	Sep. 30, 2017	Jul. 19, 2018	Apr. 30, 2018	Jan. 31, 2018
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Share repurchase program	$ 1,500,000,000		$ 5,000,000,000			$ 5,000,000,000
Shares repurchased value			$ 1,000,000,000	$ 1,000,000,000		$ 2,816,000,000	$ 1,763,000,000
Accelerated share repurchase program (payment) receipt amount	$ 30,000,000				$ 90,000,000			$ 500,000,000	$ 450,000,000	$ 150,000,000
Initial share value received								$ 400,000,000	$ 360,000,000	$ 120,000,000
Initial shares received								6,000	6,000
Shares repurchased during the period (in shares)	3,000		15,000	20,000	7,000	46,000	35,000
Subsequent Event
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Accelerated share repurchase program (payment) receipt amount		$ 100,000,000
Shares repurchased during the period (in shares)		7,000
Employee Stock Option
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities			7	10,000

Share-Based Compensation - Narr

Share-Based Compensation - Narrative (Details)	Feb. 06, 2018shares	Mar. 06, 2017employee	Feb. 28, 2018$ / sharesshares	Dec. 31, 2017shares	Sep. 30, 2018$ / shares	Sep. 30, 2017$ / sharesshares	Sep. 30, 2018$ / sharesshares	Sep. 30, 2017USD ($)$ / shares	May 31, 2018USD ($)shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted (in shares)			950,000			0
Fair value of stock options (in dollars per share) | $ / shares			$ 14.55
2017 - 2019 LTIP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of payout subject to downward adjustment (up to)							25.00%
2017 - 2019 LTIP | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payout range for participants (as a percent)							0.00%
2017 - 2019 LTIP | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payout range for participants (as a percent)							200.00%
Equity Award Modifications
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of employees impacted (employees) | employee		70
Share-based compensation expense revaluation of awards | $								$ 31,000,000
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock registered for ESPP (in shares)									4,000,000
Maximum stock value available for purchase | $									$ 25,000
Employee Stock Purchase Plan | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum payroll deduction (as a percent)									1.00%
Employee Stock Purchase Plan | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum payroll deduction (as a percent)									10.00%
Performance Units | 2017 - 2019 LTIP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted (in shares)			350,000			0
Percentage of grants with performance vesting, operating ratio (as a percent)							50.00%
Percentage of grants with performance vesting, return on assets (as a percent)							50.00%
Performance unit equivalent of CSX common stock (in shares)							1
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted (in shares)						0
Award vesting period (in years)	3 years
Restricted Stock Units (RSUs) | 2017 - 2019 LTIP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted (in shares)	85,000
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of stock options (in dollars per share) | $ / shares					$ 20.52	$ 0	$ 14.65	$ 12.83
Term of stock options (in years)			10 years
Award vesting period (in years)			3 years
Chief Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options forfeited (in shares)				9,000,000

Share-Based Compensation - Shar

Share-Based Compensation - Share-Based Compensation and Related Income Tax Benefit (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-Based Compensation Expense	$ 13	$ 19	$ 38	$ 101
Income Tax Benefit	6	12	23	41
Performance Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-Based Compensation Expense	8	3	22	41
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-Based Compensation Expense	4	14	10	47
Restricted Stock Units and Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-Based Compensation Expense	1	2	4	11
Stock Awards for Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-Based Compensation Expense	$ 0	$ 0	$ 2	$ 2

Share-Based Compensation - Sche

Share-Based Compensation - Schedule of Weighted Average Assumptions (Details) - Performance Units	3 Months Ended	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual dividend yield (as a percent)	1.20%	1.60%
Risk-free interest rate (as a percent)	2.70%	2.30%
Annualized volatility (as a percent)	27.90%	29.10%
Expected life (in years)	2 years 3 months	2 years 11 months

Share-Based Compensation - Summ

Share-Based Compensation - Summary of Fair Value Assumptions for Stock Option Awards (Details) - $ / shares	1 Months Ended	3 Months Ended		9 Months Ended
	Feb. 28, 2018	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant date fair value (in dollars per share)	$ 14.55
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant date fair value (in dollars per share)		$ 20.52	$ 0	$ 14.65	$ 12.83
Stock options valuation assumptions:
Annual dividend yield (as a percent)		1.20%	0.00%	1.50%	1.50%
Risk-free interest rate (as a percent)		2.80%	0.00%	2.60%	2.20%
Annualized volatility (as a percent)		25.50%	0.00%	27.00%	27.10%
Expected life (in years)		6 years 6 months	0 years	6 years 6 months	6 years 3 months
Other pricing model inputs:
Weighted-average grant-date market price of CSX stock (in dollars per share)		$ 74.84	$ 0	$ 54.19	$ 49.60

Casualty, Environmental and O_3

Casualty, Environmental and Other Reserves - Schedule of Casualty, Environmental and Other Reserves (Details) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Loss Contingencies [Line Items]
Current	$ 110	$ 108
Long-term	231	266
Total	341	374
Total Casualty
Loss Contingencies [Line Items]
Current	49	49
Long-term	155	179
Total	204	228
Personal Injury
Loss Contingencies [Line Items]
Current	42	43
Long-term	108	125
Total	150	168
Occupational
Loss Contingencies [Line Items]
Current	7	6
Long-term	47	54
Total	54	60
Environmental
Loss Contingencies [Line Items]
Current	37	31
Long-term	52	59
Total	89	90
Other
Loss Contingencies [Line Items]
Current	24	28
Long-term	24	28
Total	$ 48	$ 56

Casualty, Environmental and O_4

Casualty, Environmental and Other Reserves - Narrative (Details)	1 Months Ended	2 Months Ended
	Jun. 30, 2018USD ($)	May 31, 2018USD ($)	Sep. 30, 2018USD ($)claimsite	Dec. 31, 2017USD ($)
All Contingencies Reserves [Line Items]
Total reserves			$ 341,000,000	$ 374,000,000
Casualty
All Contingencies Reserves [Line Items]
Total reserves			$ 204,000,000	228,000,000
Self-insured retention amount, per occurrence	$ 75,000,000	$ 50,000,000
Number of individual claims expected to exceed self insured retention amount | claim			0
Environmental
All Contingencies Reserves [Line Items]
Total reserves			$ 89,000,000	90,000,000
Environmental impaired sites | site			216
Other
All Contingencies Reserves [Line Items]
Total reserves			$ 48,000,000	$ 56,000,000

Commitments and Contingencies (

Commitments and Contingencies (Details)	1 Months Ended			2 Months Ended	9 Months Ended
	Jun. 30, 2018USD ($)	Mar. 31, 2016defendantmi	May 31, 2007entity	May 31, 2018USD ($)	Sep. 30, 2018USD ($)claimmi
Loss Contingencies [Line Items]
Casualty and catastrophic property deductible					$ 50,000,000
Casualty and non catastrophic property deductible					$ 25,000,000
Environmental
Loss Contingencies [Line Items]
Number of miles pertaining to Passaic River tidal reach required to be studied by EPA | mi					17
Pending Litigation
Loss Contingencies [Line Items]
Claims with potential material impact (number of claims) | claim					1
Pending Litigation | Fuel Surcharge Antitrust Litigation
Loss Contingencies [Line Items]
Class action lawsuits filed against U.S.-based Class I railroads, excluding CSXT (number of entities) | entity			3
Pending Litigation | Minimum
Loss Contingencies [Line Items]
Possible loss for certain legal proceedings					$ 2,000,000
Pending Litigation | Maximum
Loss Contingencies [Line Items]
Possible loss for certain legal proceedings					$ 118,000,000
Settled Litigation | Environmental
Loss Contingencies [Line Items]
Number of miles subject to remediation | mi		8
Number of parties | defendant		80
Total Casualty
Loss Contingencies [Line Items]
Self-insured retention amount, per occurrence	$ 75,000,000			$ 50,000,000

Employee Benefit Plans - Compon

Employee Benefit Plans - Components of Expense/(Income) Related to Net Benefit Expense (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Pension Benefits
Components of expense/ (income) related to net benefit expense:
Service Cost Included in Labor and Fringe	$ 8	$ 8	$ 24	$ 28
Interest Cost	23	23	69	69
Expected Return on Plan Assets	(44)	(43)	(131)	(128)
Amortization of Net Loss	10	10	30	31
Total Income Included in Other Income - Net	(11)	(10)	(32)	(28)
Net Periodic Benefit Cost	(3)	(2)	(8)	0
Restructuring Charges - Non Operating	0	0	0	57
Total (Income) Expense	(3)	(2)	(8)	57
Other Post-retirement Benefits
Components of expense/ (income) related to net benefit expense:
Service Cost Included in Labor and Fringe	0	0	1	1
Interest Cost	2	2	5	6
Total Income Included in Other Income - Net	2	2	5	6
Net Periodic Benefit Cost	2	2	6	7
Restructuring Charges - Non Operating	0	0	0	13
Total (Income) Expense	$ 2	$ 2	$ 6	$ 20

Employee Benefit Plans - Narrat

Employee Benefit Plans - Narrative (Details)	Sep. 30, 2018USD ($)
Retirement Benefits [Abstract]
Contributions expected to plan	$ 0

Debt and Credit Agreements - Ac

Debt and Credit Agreements - Activity Related to Long-Term Debt (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Movement, Debt Instruments [Roll Forward]
Beginning balance, current portion	$ 19
Beginning balance, long-term portion	11,790
Beginning balance, total	11,809
Long-term debt issued	2,000	$ 850
Long-term debt repaid	(19)
Reclassifications	0
Discount, premium and other activity	(18)
Ending balance, current portion	18
Ending balance, long-term portion	13,754
Ending balance, total	13,772
Current Portion
Movement, Debt Instruments [Roll Forward]
Beginning balance, current portion	19
Long-term debt issued	0
Long-term debt repaid	(19)
Reclassifications	18
Discount, premium and other activity	0
Ending balance, current portion	18
Long-term Portion
Movement, Debt Instruments [Roll Forward]
Beginning balance, long-term portion	11,790
Long-term debt issued	2,000
Long-term debt repaid	0
Reclassifications	(18)
Discount, premium and other activity	(18)
Ending balance, long-term portion	$ 13,754

Debt and Credit Agreements - Na

Debt and Credit Agreements - Narrative (Details) - USD ($)	Feb. 20, 2018	Sep. 30, 2018	Sep. 30, 2017	Sep. 14, 2018
Line of Credit Facility
Long-term debt issued		$ 2,000,000,000	$ 850,000,000
Commercial Paper
Line of Credit Facility
Maximum borrowing capacity				$ 1,000,000,000
Outstanding balance		0
Notes due 2028
Line of Credit Facility
Long-term debt issued	$ 800,000,000
Interest rate (as a percent)	3.80%
Notes due 2048
Line of Credit Facility
Long-term debt issued	$ 850,000,000
Interest rate (as a percent)	4.30%
Notes due 2068
Line of Credit Facility
Long-term debt issued	$ 350,000,000
Interest rate (as a percent)	4.65%
Unsecured Revolving Credit Facility | Credit Facility
Line of Credit Facility
Maximum borrowing capacity		$ 1,000,000,000
Facility expiration date		May 21, 2020
Amount outstanding		$ 0
Receivables Securitization Facility | Line of Credit
Line of Credit Facility
Maximum borrowing capacity		200,000,000
Outstanding balance		$ 0
Facility expiration date		Sep. 1, 2019
Facility expiration period		3 years

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Millions	9 Months Ended		12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Effective tax rate (as a percent)	23.10%	38.40%
Unrecognized tax benefits increase			$ 0
Unrecognized tax benefits decrease			$ 0

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of Fair Value of Investment Assets (Details) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Amortized cost basis	$ 705	$ 95
Fair Value | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments fair value disclosure	706	95
Fair Value | Level 2 | Certificates of Deposit and Commercial Paper
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments fair value disclosure	610	0
Fair Value | Level 2 | Corporate Bonds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments fair value disclosure	56	61
Fair Value | Level 2 | Government Securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments fair value disclosure	$ 40	$ 34

Fair Value Measurements - Sch_2

Fair Value Measurements - Schedule of Investment Maturities (Details) - Fair Value - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Less than 1 year	$ 615	$ 18
1 - 5 years	17	11
5 - 10 years	25	26
Greater than 10 years	49	40
Total investments at fair value	$ 706	$ 95

Fair Value Measurements - Sch_3

Fair Value Measurements - Schedule of Fair Value and Carrying Value of Long-Term Debt (Details) - Level 2 - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term Debt (Including Current Maturities):	$ 14,173	$ 13,220
Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term Debt (Including Current Maturities):	$ 13,772	$ 11,809

Other Comprehensive Income (L_3

Other Comprehensive Income (Loss) - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Equity [Abstract]
Total comprehensive earnings, net of tax	$ 901	$ 467	$ 2,378	$ 1,410

Other Comprehensive Income (L_4

Other Comprehensive Income (Loss) - Changes in AOCI balance by Component (Details) $ in Millions	9 Months Ended
	Sep. 30, 2018USD ($)
Other Comprehensive Income (Loss)
Loss Before Reclassifications	$ (2)
Amounts Reclassified to Net Earnings	27
Tax (Expense) Benefit	(6)
Reclassification of Stranded Tax Effects	(107)
Total Other Comprehensive Loss	(88)
Pension and Other Post-Employment Benefits
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(440)
Other Comprehensive Income (Loss)
Loss Before Reclassifications	0
Amounts Reclassified to Net Earnings	31
Tax (Expense) Benefit	(7)
Reclassification of Stranded Tax Effects	(108)
Total Other Comprehensive Loss	(84)
Ending balance	(524)
Other
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(46)
Other Comprehensive Income (Loss)
Loss Before Reclassifications	(2)
Amounts Reclassified to Net Earnings	(4)
Tax (Expense) Benefit	1
Reclassification of Stranded Tax Effects	1
Total Other Comprehensive Loss	(4)
Ending balance	(50)
Accumulated Other Comprehensive Income (Loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(486)
Other Comprehensive Income (Loss)
Ending balance	$ (574)

Revenues - Schedule of Revenues

Revenues - Schedule of Revenues Disaggregated by Lines of Business (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Disaggregation of Revenue [Line Items]
Revenues	$ 3,129	$ 2,743	$ 9,107	$ 8,545
Total Merchandise
Disaggregation of Revenue [Line Items]
Revenues	1,890	1,688	5,576	5,325
Chemicals
Disaggregation of Revenue [Line Items]
Revenues	596	546	1,741	1,664
Agricultural and Food Products
Disaggregation of Revenue [Line Items]
Revenues	325	288	959	941
Automotive
Disaggregation of Revenue [Line Items]
Revenues	300	269	934	892
Forest Products
Disaggregation of Revenue [Line Items]
Revenues	223	181	633	567
Metals and Equipment
Disaggregation of Revenue [Line Items]
Revenues	205	178	589	546
Minerals
Disaggregation of Revenue [Line Items]
Revenues	137	120	388	362
Fertilizers
Disaggregation of Revenue [Line Items]
Revenues	104	106	332	353
Total Coal
Disaggregation of Revenue [Line Items]
Revenues	588	514	1,660	1,566
Domestic Coal
Disaggregation of Revenue [Line Items]
Revenues	347	350	937	1,029
Export Coal
Disaggregation of Revenue [Line Items]
Revenues	241	164	723	537
Total Intermodal
Disaggregation of Revenue [Line Items]
Revenues	500	446	1,439	1,328
Domestic Intermodal
Disaggregation of Revenue [Line Items]
Revenues	331	297	948	896
International Intermodal
Disaggregation of Revenue [Line Items]
Revenues	169	149	491	432
Other
Disaggregation of Revenue [Line Items]
Revenues	$ 151	$ 95	$ 432	$ 326

Revenues - Narrative (Details)

Revenues - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Contract payment period			15 days
Remaining performance obligation	$ 0		$ 0
Contract assets	0		0
Contract liabilities	0		$ 0
Impairment loss	$ 0	$ 0
Minimum
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Transit time			3 days
Maximum
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Transit time			8 days
Customer Concentration Risk | Sales Revenue
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue from other services (as a percent)	5.00%

Revenues - Schedule of Accounts

Revenues - Schedule of Accounts Receivable (Details) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Accounts Receivable, net	$ 1,090	$ 970
Freight Receivables
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivables gross	887	810
Allowance for Doubtful Accounts	(17)	(17)
Total Accounts Receivable, net	870	793
Non-Freight Receivables
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivables gross	230	186
Allowance for Doubtful Accounts	(10)	(9)
Total Accounts Receivable, net	$ 220	$ 177

Summarized Consolidating Fina_3

Summarized Consolidating Financial Data - Consolidating Income Statements (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Consolidated Income Statement
Revenues	$ 3,129	$ 2,743	$ 9,107	$ 8,545
Operating Expenses	1,836	1,875	5,487	5,951
Operating Income	1,293	868	3,620	2,594
Equity in Earnings of Subsidiaries	0	0	0	0
Interest (Expense) / Benefit	(162)	(132)	(468)	(406)
Other Income / (Expense) - Net	19	14	54	(29)
Earnings Before Income Taxes	1,150	750	3,206	2,159
Income Tax Benefit / (Expense)	(256)	(291)	(740)	(828)
Net Earnings	894	459	2,466	1,331
Total Comprehensive Earnings	901	467	2,378	1,410
Eliminations and Other
Consolidated Income Statement
Revenues	19	18	57	55
Operating Expenses	(30)	(27)	(108)	(103)
Operating Income	49	45	165	158
Equity in Earnings of Subsidiaries	(953)	(472)	(2,653)	(1,506)
Interest (Expense) / Benefit	39	18	95	47
Other Income / (Expense) - Net	(22)	(6)	(49)	(14)
Earnings Before Income Taxes	(887)	(415)	(2,442)	(1,315)
Income Tax Benefit / (Expense)	(17)	(18)	(48)	(64)
Net Earnings	(904)	(433)	(2,490)	(1,379)
Total Comprehensive Earnings	(903)	(433)	(2,484)	(1,378)
CSX Corporation
Consolidated Income Statement
Revenues	0	0	0	0
Operating Expenses	(86)	(129)	(248)	(171)
Operating Income	86	129	248	171
Equity in Earnings of Subsidiaries	953	472	2,653	1,506
Interest (Expense) / Benefit	(190)	(147)	(535)	(432)
Other Income / (Expense) - Net	6	1	16	6
Earnings Before Income Taxes	855	455	2,382	1,251
Income Tax Benefit / (Expense)	39	4	84	80
Net Earnings	894	459	2,466	1,331
Total Comprehensive Earnings	901	467	2,378	1,410
CSX Transportation
Consolidated Income Statement
Revenues	3,110	2,725	9,050	8,490
Operating Expenses	1,952	2,031	5,843	6,225
Operating Income	1,158	694	3,207	2,265
Equity in Earnings of Subsidiaries	0	0	0	0
Interest (Expense) / Benefit	(11)	(3)	(28)	(21)
Other Income / (Expense) - Net	35	19	87	(21)
Earnings Before Income Taxes	1,182	710	3,266	2,223
Income Tax Benefit / (Expense)	(278)	(277)	(776)	(844)
Net Earnings	904	433	2,490	1,379
Total Comprehensive Earnings	$ 903	$ 433	$ 2,484	$ 1,378

Summarized Consolidating Fina_4

Summarized Consolidating Financial Data - Consolidating Balance Sheet (Details) - USD ($) $ / shares in Units, $ in Millions	Sep. 30, 2018	Dec. 31, 2017	Sep. 30, 2017	Dec. 30, 2016
Current Assets:
Cash and Cash Equivalents	$ 663	$ 401	$ 591	$ 603
Short-term Investments	615	18
Accounts Receivable - Net	1,090	970
Receivable from Affiliates	0	0
Materials and Supplies	283	372
Other Current Assets	133	154
Total Current Assets	2,784	1,915
Properties	44,485	44,324
Accumulated Depreciation	(12,614)	(12,560)
Properties - Net	31,871	31,764
Other Long-term Assets	442	374
Total Assets	36,861	35,739
Current Liabilities:
Accounts Payable	982	847
Labor and Fringe Benefits Payable	517	602
Payable to Affiliates	0	0
Casualty, Environmental and Other Reserves	110	108
Current Maturities of Long-term Debt	18	19
Income and Other Taxes Payable	166	157
Other Current Liabilities	151	161
Total Current Liabilities	1,944	1,894
Casualty, Environmental and Other Reserves	231	266
Long-term Debt	13,754	11,790
Deferred Income Taxes - Net	6,584	6,418
Other Long-term Liabilities	613	650
Total Liabilities	23,126	21,018
Shareholders' Equity
Common Stock, $1 Par Value	844	890
Other Capital	129	217
Retained Earnings	13,320	14,084
Accumulated Other Comprehensive Loss	(574)	(486)
Noncontrolling Interest	16	16
Total Shareholders' Equity	13,735	14,721
Total Liabilities and Shareholders' Equity	$ 36,861	$ 35,739
Common stock, par value (in dollars per share)	$ 1	$ 1
Investments in Conrail
Current Assets:
Investment in Affiliates and Other Companies	$ 941	$ 907
Affiliates and Other Companies
Current Assets:
Investment in Affiliates and Other Companies	823	779
Investments in Consolidated Subsidiaries
Current Assets:
Investment in Affiliates and Other Companies	0	0
Eliminations and Other
Current Assets:
Cash and Cash Equivalents	10	6	11	17
Short-term Investments	5	18
Accounts Receivable - Net	868	670
Receivable from Affiliates	(6,216)	(4,743)
Materials and Supplies	0	0
Other Current Assets	18	10
Total Current Assets	(5,315)	(4,039)
Properties	2,855	2,844
Accumulated Depreciation	(1,570)	(1,542)
Properties - Net	1,285	1,302
Other Long-term Assets	(248)	(261)
Total Assets	(34,609)	(31,478)
Current Liabilities:
Accounts Payable	40	34
Labor and Fringe Benefits Payable	43	56
Payable to Affiliates	(6,736)	(5,344)
Casualty, Environmental and Other Reserves	13	13
Current Maturities of Long-term Debt	0	0
Income and Other Taxes Payable	39	28
Other Current Liabilities	2	3
Total Current Liabilities	(6,599)	(5,210)
Casualty, Environmental and Other Reserves	40	44
Long-term Debt	0	1
Deferred Income Taxes - Net	199	206
Other Long-term Liabilities	(304)	(314)
Total Liabilities	(6,664)	(5,273)
Shareholders' Equity
Common Stock, $1 Par Value	(181)	(181)
Other Capital	(5,096)	(5,096)
Retained Earnings	(22,679)	(20,933)
Accumulated Other Comprehensive Loss	11	5
Noncontrolling Interest	0	0
Total Shareholders' Equity	(27,945)	(26,205)
Total Liabilities and Shareholders' Equity	(34,609)	(31,478)
Eliminations and Other | Investments in Conrail
Current Assets:
Investment in Affiliates and Other Companies	941	907
Eliminations and Other | Affiliates and Other Companies
Current Assets:
Investment in Affiliates and Other Companies	16	18
Eliminations and Other | Investments in Consolidated Subsidiaries
Current Assets:
Investment in Affiliates and Other Companies	(31,288)	(29,405)
CSX Corporation
Current Assets:
Cash and Cash Equivalents	537	274	433	305
CSX Corporation | Corporate, Non-Segment
Current Assets:
Cash and Cash Equivalents	537	274
Short-term Investments	610	0
Accounts Receivable - Net	1	(1)
Receivable from Affiliates	960	1,226
Materials and Supplies	0	0
Other Current Assets	0	(1)
Total Current Assets	2,108	1,498
Properties	1	1
Accumulated Depreciation	(1)	(1)
Properties - Net	0	0
Other Long-term Assets	77	39
Total Assets	33,434	30,903
Current Liabilities:
Accounts Payable	189	105
Labor and Fringe Benefits Payable	40	52
Payable to Affiliates	6,339	4,792
Casualty, Environmental and Other Reserves	0	0
Current Maturities of Long-term Debt	0	0
Income and Other Taxes Payable	(415)	(326)
Other Current Liabilities	1	5
Total Current Liabilities	6,154	4,628
Casualty, Environmental and Other Reserves	0	0
Long-term Debt	13,043	11,056
Deferred Income Taxes - Net	(99)	(130)
Other Long-term Liabilities	617	644
Total Liabilities	19,715	16,198
Shareholders' Equity
Common Stock, $1 Par Value	844	890
Other Capital	129	217
Retained Earnings	13,320	14,084
Accumulated Other Comprehensive Loss	(574)	(486)
Noncontrolling Interest	0	0
Total Shareholders' Equity	13,719	14,705
Total Liabilities and Shareholders' Equity	33,434	30,903
CSX Corporation | Corporate, Non-Segment | Investments in Conrail
Current Assets:
Investment in Affiliates and Other Companies	0	0
CSX Corporation | Corporate, Non-Segment | Affiliates and Other Companies
Current Assets:
Investment in Affiliates and Other Companies	(39)	(39)
CSX Corporation | Corporate, Non-Segment | Investments in Consolidated Subsidiaries
Current Assets:
Investment in Affiliates and Other Companies	31,288	29,405
CSX Transportation
Current Assets:
Cash and Cash Equivalents	116	121	$ 147	$ 281
Short-term Investments	0	0
Accounts Receivable - Net	221	301
Receivable from Affiliates	5,256	3,517
Materials and Supplies	283	372
Other Current Assets	115	145
Total Current Assets	5,991	4,456
Properties	41,629	41,479
Accumulated Depreciation	(11,043)	(11,017)
Properties - Net	30,586	30,462
Other Long-term Assets	613	596
Total Assets	38,036	36,314
Current Liabilities:
Accounts Payable	753	708
Labor and Fringe Benefits Payable	434	494
Payable to Affiliates	397	552
Casualty, Environmental and Other Reserves	97	95
Current Maturities of Long-term Debt	18	19
Income and Other Taxes Payable	542	455
Other Current Liabilities	148	153
Total Current Liabilities	2,389	2,476
Casualty, Environmental and Other Reserves	191	222
Long-term Debt	711	733
Deferred Income Taxes - Net	6,484	6,342
Other Long-term Liabilities	300	320
Total Liabilities	10,075	10,093
Shareholders' Equity
Common Stock, $1 Par Value	181	181
Other Capital	5,096	5,096
Retained Earnings	22,679	20,933
Accumulated Other Comprehensive Loss	(11)	(5)
Noncontrolling Interest	16	16
Total Shareholders' Equity	27,961	26,221
Total Liabilities and Shareholders' Equity	38,036	36,314
CSX Transportation | Investments in Conrail
Current Assets:
Investment in Affiliates and Other Companies	0	0
CSX Transportation | Affiliates and Other Companies
Current Assets:
Investment in Affiliates and Other Companies	846	800
CSX Transportation | Investments in Consolidated Subsidiaries
Current Assets:
Investment in Affiliates and Other Companies	$ 0	$ 0

Summarized Consolidating Fina_5

Summarized Consolidating Financial Data - Consolidating Cash Flow Statements (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Operating Activities
Net Cash Provided by (Used in) Operating Activities			$ 3,406	$ 2,861
Investing Activities
Property Additions			(1,240)	(1,462)
Proceeds from Property Dispositions			257	38
Purchase of Short-term Investments			(611)	(645)
Proceeds from Sales of Short-term Investments			15	957
Other Investing Activities			(8)	33
Net Cash Used In Investing Activities			(1,587)	(1,079)
Financing Activities
Long-term Debt Issued			2,000	850
Long-term Debt Repaid			(19)	(332)
Dividends Paid			(570)	(530)
Shares Repurchased	$ (1,000)	$ (1,000)	(2,816)	(1,763)
Accelerated Share Repurchase Pending Final Settlement (Note 2)			(100)	0
Other Financing Activities			(52)	(19)
Net Cash Used in Financing Activities			(1,557)	(1,794)
Net Increase (Decrease) in Cash and Cash Equivalents			262	(12)
Cash and Cash Equivalents at Beginning of Period			401	603
Cash and Cash Equivalents at End of Period	663	591	663	591
Eliminations and Other
Operating Activities
Net Cash Provided by (Used in) Operating Activities			(803)	(273)
Investing Activities
Property Additions			(106)	(151)
Proceeds from Property Dispositions			0	0
Purchase of Short-term Investments			(2)	(6)
Proceeds from Sales of Short-term Investments			15	2
Other Investing Activities			142	(25)
Net Cash Used In Investing Activities			49	(180)
Financing Activities
Long-term Debt Issued			0	0
Long-term Debt Repaid			0	0
Dividends Paid			750	450
Shares Repurchased			0	0
Accelerated Share Repurchase Pending Final Settlement (Note 2)			0
Other Financing Activities			8	(3)
Net Cash Used in Financing Activities			758	447
Net Increase (Decrease) in Cash and Cash Equivalents			4	(6)
Cash and Cash Equivalents at Beginning of Period			6	17
Cash and Cash Equivalents at End of Period	10	11	10	11
CSX Corporation
Operating Activities
Net Cash Provided by (Used in) Operating Activities			2,417	1,590
Investing Activities
Property Additions			0	0
Proceeds from Property Dispositions			0	0
Purchase of Short-term Investments			(609)	(639)
Proceeds from Sales of Short-term Investments			0	955
Other Investing Activities			(1)	(2)
Net Cash Used In Investing Activities			(610)	314
Financing Activities
Long-term Debt Issued			2,000	850
Long-term Debt Repaid			0	(312)
Dividends Paid			(570)	(530)
Shares Repurchased			(2,816)	(1,763)
Accelerated Share Repurchase Pending Final Settlement (Note 2)			(100)
Other Financing Activities			(58)	(21)
Net Cash Used in Financing Activities			(1,544)	(1,776)
Net Increase (Decrease) in Cash and Cash Equivalents			263	128
Cash and Cash Equivalents at Beginning of Period			274	305
Cash and Cash Equivalents at End of Period	537	433	537	433
CSX Transportation
Operating Activities
Net Cash Provided by (Used in) Operating Activities			1,792	1,544
Investing Activities
Property Additions			(1,134)	(1,311)
Proceeds from Property Dispositions			257	38
Purchase of Short-term Investments			0	0
Proceeds from Sales of Short-term Investments			0	0
Other Investing Activities			(149)	60
Net Cash Used In Investing Activities			(1,026)	(1,213)
Financing Activities
Long-term Debt Issued			0	0
Long-term Debt Repaid			(19)	(20)
Dividends Paid			(750)	(450)
Shares Repurchased			0	0
Accelerated Share Repurchase Pending Final Settlement (Note 2)			0
Other Financing Activities			(2)	5
Net Cash Used in Financing Activities			(771)	(465)
Net Increase (Decrease) in Cash and Cash Equivalents			(5)	(134)
Cash and Cash Equivalents at Beginning of Period			121	281
Cash and Cash Equivalents at End of Period	$ 116	$ 147	$ 116	$ 147