Kirby (KEX) 10-K 26 Feb 19 2018 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2018	Feb. 22, 2019	Jun. 30, 2018
Document and Entity Information [Abstract]
Entity Registrant Name	KIRBY CORP
Entity Central Index Key	56,047
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Shell Company	false
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Ex Transition Period	false
Entity Public Float			$ 4,907,213,000
Entity Common Stock, Shares Outstanding		59,875,000
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	FY

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 7,800	$ 20,102
Accounts receivable:
Trade - less allowance for doubtful accounts of $10,024 ($8,930 in 2017)	417,644	452,222
Other	104,239	106,231
Inventories - at lower of average cost or market	507,441	315,729
Prepaid expenses and other current assets	59,365	62,798
Total current assets	1,096,489	957,082
Property and equipment:
Marine transportation equipment	4,477,718	3,848,334
Land, buildings and equipment	534,106	512,548
Property and equipment	5,011,824	4,360,882
Accumulated depreciation	1,472,022	1,401,617
Property and equipment - net	3,539,802	2,959,265
Investment in affiliates	2,495	1,890
Goodwill	953,826	935,135
Other intangibles - net	224,197	232,808
Other assets	54,785	41,247
Total assets	5,871,594	5,127,427
Current liabilities:
Bank notes payable	19	3
Income taxes payable	2,794	191
Accounts payable	278,057	222,005
Accrued liabilities:
Interest	13,171	6,099
Insurance premiums and claims	109,634	108,651
Employee compensation	53,089	45,193
Taxes - other than on income	38,680	22,791
Other	32,215	27,026
Deferred revenues	80,123	48,347
Total current liabilities	607,782	480,306
Long-term debt - less current portion	1,410,169	992,403
Deferred income taxes	542,785	468,451
Other long-term liabilities	94,557	72,044
Total long-term liabilities	2,047,511	1,532,898
Contingencies and commitments
Kirby stockholders' equity:
Common stock, $.10 par value per share. Authorized 120,000,000 shares, issued 65,472,000 in 2018 and 2017	6,547	6,547
Additional paid-in capital	823,347	802,961
Accumulated other comprehensive income - net	(33,511)	(32,405)
Retained earnings	2,723,592	2,646,937
Treasury stock - at cost, 5,608,000 shares in 2018 and 5,783,000 shares in 2017	(306,788)	(313,220)
Total Kirby stockholders' equity	3,213,187	3,110,820
Noncontrolling interests	3,114	3,403
Total equity	3,216,301	3,114,223
Total liabilities and equity	$ 5,871,594	$ 5,127,427

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Current assets:
Trade, allowance for doubtful accounts	$ 10,024	$ 8,930
Kirby stockholders' equity:
Common stock, par value per share (in dollars per share)	$ 0.10	$ 0.10
Common stock, shares authorized (in shares)	120,000,000	120,000,000
Common stock, shares issued (in shares)	65,472,000	65,472,000
Treasury stock, shares (in shares)	5,608,000	5,783,000

CONSOLIDATED STATEMENTS OF EARN

CONSOLIDATED STATEMENTS OF EARNINGS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Revenues:
Total revenues	$ 2,970,697	$ 2,214,418	$ 1,770,673
Costs and expenses:
Costs of sales and operating expenses	2,160,946	1,558,098	1,124,666
Selling, general and administrative	304,397	220,452	174,863
Taxes, other than on income	39,251	29,163	22,730
Depreciation and amortization	224,972	202,881	200,917
Impairment of long-lived assets	82,705	105,712	0
Impairment of goodwill	2,702	0	0
Lease cancellation costs	2,403	0	0
Loss (gain) on disposition of assets	(1,968)	4,487	127
Total costs and expenses	2,815,408	2,120,793	1,523,303
Operating income	155,289	93,625	247,370
Equity in earnings of affiliates	355	291	532
Other income (expense)	5,371	570	(2,466)
Interest expense	(46,856)	(21,472)	(17,690)
Earnings before taxes on income	114,159	73,014	227,746
Benefit (provision) for taxes on income	(35,081)	240,889	(84,942)
Net earnings	79,078	313,903	142,804
Less: Net earnings attributable to noncontrolling interests	(626)	(716)	(1,398)
Net earnings attributable to Kirby	$ 78,452	$ 313,187	$ 141,406
Net earnings per share attributable to Kirby common stockholders:
Basic (in dollars per share)	$ 1.31	$ 5.62	$ 2.63
Diluted (in dollars per share)	$ 1.31	$ 5.62	$ 2.62
Marine Transportation [Member]
Revenues:
Total revenues	$ 1,483,143	$ 1,324,106	$ 1,471,893
Distribution and Services [Member]
Revenues:
Total revenues	$ 1,487,554	$ 890,312	$ 298,780

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME [Abstract]
Net earnings	$ 79,078	$ 313,903	$ 142,804
Other comprehensive income (loss), net of taxes:
Pension and postretirement benefits	7,638	18,748	(6,321)
Foreign currency translation adjustments	(819)	(146)	0
Reclassification to retained earnings of stranded tax effects from tax reform	(7,925)	0	0
Total other comprehensive income (loss), net of taxes	(1,106)	18,602	(6,321)
Total comprehensive income, net of taxes	77,972	332,505	136,483
Net earnings attributable to noncontrolling interests	(626)	(716)	(1,398)
Comprehensive income attributable to Kirby	$ 77,346	$ 331,789	$ 135,085

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cash flows from operating activities:
Net earnings	$ 79,078	$ 313,903	$ 142,804
Adjustments to reconcile net earnings to net cash provided by operations:
Depreciation and amortization	224,972	202,881	200,917
Provision (credit) for doubtful accounts	1,289	224	(467)
Provision (benefit) for deferred income taxes	34,881	(256,263)	51,296
Loss (gain) on disposition of assets	(1,968)	4,487	127
Equity in earnings of affiliates, net of distributions and contributions	(355)	732	(532)
Impairment of long-lived assets	82,705	105,712	0
Impairment of goodwill	2,702	0	0
Amortization of unearned share-based compensation	19,104	11,460	11,675
Amortization of major maintenance costs	20,760	21,207	19,869
Amortization of debt issuance costs	1,218	986	801
Increase (decrease) in cash flows resulting from changes in:
Accounts receivable	12,511	(60,405)	(12,750)
Inventory	(144,685)	19,673	3,182
Other assets	(38,090)	(17,049)	(30,853)
Income taxes payable	(457)	(11,823)	15,413
Accounts payable	22,622	20,758	(1,739)
Accrued and other liabilities	30,712	(3,105)	16,051
Net cash provided by operating activities	346,999	353,378	415,794
Cash flows from investing activities:
Capital expenditures	(301,861)	(177,222)	(231,066)
Acquisitions of businesses and marine equipment, net of cash acquired	(533,897)	(470,101)	(137,072)
Proceeds from disposition of assets	53,392	54,229	18,617
Other	(250)	0	0
Net cash used in investing activities	(782,616)	(593,094)	(349,521)
Cash flows from financing activities:
Borrowings (payments) on bank credit facilities, net	(78,455)	269,859	(52,848)
Borrowings (payments) on long-term debt	499,295	(13,721)	0
Payment of debt issue costs	(4,276)	(1,243)	0
Return of investment to noncontrolling interests	(915)	(862)	(1,976)
Proceeds from exercise of stock options	13,264	3,039	321
Purchase of treasury stock	(776)	0	(1,827)
Payments related to tax withholding for share-based compensation	(4,822)	(2,881)	(1,756)
Acquisitions of noncontrolling interest	0	(7)	(8,438)
Net cash provided by (used in) financing activities	423,315	254,184	(66,524)
Increase (decrease) in cash and cash equivalents	(12,302)	14,468	(251)
Cash and cash equivalents, beginning of year	20,102	5,634	5,885
Cash and cash equivalents, end of year	7,800	20,102	5,634
Cash paid during the period:
Interest paid	40,772	21,663	19,878
Income taxes paid	640	27,196	18,162
Capital expenditures included in accounts payable	(16,441)	5,525	(2,037)
Non-cash investing activity:
Fair value of property transferred in acquisition	0	0	3,681
Stock issued in acquisition	0	366,554	0
Cash acquired in acquisition	2,313	98	0
Debt assumed in acquisition	$ 0	$ 13,724	$ 0

CONSOLIDATED STATEMENTS OF STOC

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Other Comprehensive Income [Member]	Retained Earnings [Member]	Treasury Stock [Member]	Noncontrolling Interests [Member]	Total
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect of adoption | ASU 2016-09 [Member]				$ 0
Cumulative effect of adoption | ASU 2014-09 [Member]				0
Cumulative effect of adoption | ASU 2018-02 [Member]			$ 0	0
Balance at beginning of year at Dec. 31, 2015	$ 5,978	$ 434,783	(44,686)	2,200,830	$ (328,094)	$ 10,385
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of shares in acquisition	0	0
(Deficit) of proceeds received upon exercise of stock options and issuance of restricted stock over cost of treasury stock issued		(755)
Tax expense realized from equity compensation plans		(824)
Issuance of restricted stock, net of forfeitures		(10,218)
Amortization of unearned compensation		11,675
Acquisitions of noncontrolling interests		(2,202)				(6,258)
Net earnings attributable to Kirby for the year				141,406			$ 141,406
Purchase of treasury stock (11,000 in 2018 and 35,000 in 2016)					(1,827)
Cost of treasury stock issued upon exercise of stock options and issuance of restricted stock (186,000 in 2018, 138,000 in 2017 and 170,000 in 2016)					9,573
Net earnings attributable to noncontrolling interests						1,398	1,398
Return of investment to noncontrolling interests						(1,976)	1,976
Other comprehensive income (loss), net of taxes			(6,321)				(6,321)
Balance at end of year at Dec. 31, 2016	5,978	432,459	(51,007)	2,342,236	(320,348)	3,549
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect of adoption | ASU 2016-09 [Member]				(8,486)
Cumulative effect of adoption | ASU 2014-09 [Member]				0
Cumulative effect of adoption | ASU 2018-02 [Member]			0	0
Issuance of shares in acquisition	569	365,985
Excess of proceeds received upon exercise of stock options and issuance of restricted stock over cost of treasury stock issued		833
Tax expense realized from equity compensation plans		0
Issuance of restricted stock, net of forfeitures		(7,770)
Amortization of unearned compensation		11,460
Acquisitions of noncontrolling interests		(6)				0
Net earnings attributable to Kirby for the year				313,187			313,187
Purchase of treasury stock (11,000 in 2018 and 35,000 in 2016)					0
Cost of treasury stock issued upon exercise of stock options and issuance of restricted stock (186,000 in 2018, 138,000 in 2017 and 170,000 in 2016)					7,128
Net earnings attributable to noncontrolling interests						716	716
Return of investment to noncontrolling interests						(862)	862
Other comprehensive income (loss), net of taxes			18,602				18,602
Balance at end of year at Dec. 31, 2017	6,547	802,961	(32,405)	2,646,937	(313,220)	3,403	3,114,223
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect of adoption | ASU 2016-09 [Member]				0
Cumulative effect of adoption | ASU 2014-09 [Member]				(9,722)
Cumulative effect of adoption | ASU 2018-02 [Member]			(7,925)	7,925
Issuance of shares in acquisition	0	0
Excess of proceeds received upon exercise of stock options and issuance of restricted stock over cost of treasury stock issued		3,489
Tax expense realized from equity compensation plans		0
Issuance of restricted stock, net of forfeitures		(2,207)
Amortization of unearned compensation		19,104
Acquisitions of noncontrolling interests		0				0
Net earnings attributable to Kirby for the year				78,452			78,452
Purchase of treasury stock (11,000 in 2018 and 35,000 in 2016)					(776)
Cost of treasury stock issued upon exercise of stock options and issuance of restricted stock (186,000 in 2018, 138,000 in 2017 and 170,000 in 2016)					7,208
Net earnings attributable to noncontrolling interests						626	626
Return of investment to noncontrolling interests						(915)	915
Other comprehensive income (loss), net of taxes			6,819				(1,106)
Balance at end of year at Dec. 31, 2018	$ 6,547	$ 823,347	$ (33,511)	2,723,592	$ (306,788)	$ 3,114	3,216,301
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect of adoption | ASU 2014-09 [Member]				$ 9,722			$ 9,722

CONSOLIDATED STATEMENTS OF ST_2

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Parenthetical) - Treasury Stock [Member] - shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Purchase of treasury stock (in shares)	11,000	0	35,000
Treasury stock issued upon exercise of stock options and issuance of restricted stock (in shares)	186,000	138,000	170,000

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2018
Summary of Significant Accounting Policies [Abstract]
Summary of Significant Accounting Policies	(1) Summary of Significant Accounting Policies Principles of Consolidation. Accounting Policies Cash Equivalents. Accounts Receivable. The Company’s marine transportation and distribution and services operations are subject to hazards associated with such businesses. The Company maintains insurance coverage against these hazards with insurance companies. Included in accounts receivable as of December 31, 2018 and 2017 were $69,624,000 and $66,588,000, respectively, of receivables from insurance companies to cover claims in excess of the Company’s deductible. Concentrations of Credit Risk. Fair Value of Financial Instruments. Property, Maintenance and Repairs. Drydocking on Ocean-Going Vessels. Environmental Liabilities. Goodwill. During the 2018 fourth quarter, the Company took a $2,702,000 charge for the impairment of the remaining goodwill recorded for Osprey Line, L.L.C., a subsidiary that transports project cargoes and cargo containers by barge on the United States inland waterway system. The impairment reflected the reduced profitability outlook of the container-on-barge operations due to the current economic environment. The fair value was determined using a combination of a discounted cash flow methodology and a market based approach utilizing a net earnings before interest expense, taxes on income, depreciation and amortization (EBITDA) multiplier. Net goodwill for the marine transportation segment was $405,575,000 and $387,504,000 at December 31, 2018 and 2017, respectively. The increase in net goodwill for the marine transportation segment for 2018 was due to the acquisitions of Higman Marine, Inc. and its affiliated companies (“Higman”) and Targa Resources Corp.’s (“Targa”) inland tank barge business, more fully described in Note 3, Acquisitions. Net goodwill for the distribution and services segment was $548,251,000 and $547,631,000 at December 31, 2018 and 2017, respectively. Other Intangibles. The costs of intangible assets and liabilities are amortized to expense in a systematic and rational manner over their estimated useful lives. For the years ended December 31, 2018, 2017 and 2016, the amortization expense for intangibles was $16,760,000, $11,296,000 and $8,467,000, respectively. Estimated amortization expense for amortizable intangible assets and liabilities for the next five years (2019 – 2023) is approximately $18,999,000, $20,854,000, $20,174,000, $19,824,000 and $19,782,000, respectively. As of December 31, 2018, the weighted average amortization period for intangible assets and liabilities was approximately 14 years. Revenue Recognition. Distribution products and services are generally sold based upon purchase orders or preferential service agreements with the customer that include fixed or determinable prices. Parts sales are recognized when control transfers to the customer, generally when title passes upon shipment to customers. Service revenue is recognized over time as the service is provided using measures of progress utilizing hours worked or costs incurred as a percentage of estimated hours or expected costs. Revenue from rental agreements is recognized on a straight-line basis over the rental period. The Company recognizes the revenues on contract manufacturing activities upon shipment and transfer of control to the customer. Prior to the adoption of Accounting Standards Update (“ASU”) Stock-Based Compensation. Taxes on Income. Accrued Insurance. Treasury Stock. Impairment of Long-lived Assets and for Long-lived Assets to Be Disposed Of. Recoverability on marine transportation assets is assessed based on vessel classes, not on individual assets, because identifiable cash flows for individual marine transportation assets are not available. Projecting customer contract volumes allows estimation of future cash flows by projecting pricing and utilization by vessel class but it is not practical to project which individual marine transportation asset will be utilized for any given contract. Because customers do not specify which particular vessel is used, prices are quoted based on vessel classes not individual assets. Nominations of vessels for specific jobs are determined on a day by day basis and are a function of the equipment class required and the geographic position of vessels within that class at that particular time as vessels within a class are interchangeable and provide the same service. The Company’s vessels are mobile assets and equipped to operate in geographic regions throughout the United States and the Company has in the past and expects to continue to move vessels from one region to another when it is necessary due to changing markets and it is economical to do so. Barge vessel classes are based on similar capacities, hull type, and type of product and towing vessels are based on similar hull type and horsepower. Recoverability of the vessel classes is measured by a comparison of the carrying amount of the assets to future net cash flows expected to be generated by the assets. If such assets are considered to be impaired, the impairment to be recognized is measured by the amount by which the carrying amount of the assets exceeds the fair value of the assets. Assets to be disposed of are reported at the lower of the carrying amount or fair value less costs to sell. Accounting Standards In August 2018, the Financial Accounting Standards Board (“FASB”) issued ASU 2018-14, “Compensation – Retirement Benefits - Defined Benefit Plans – General (Subtopic 715-20): Disclosure Framework – Changes to the Disclosure Requirements for Defined Benefit Plans” which amends the annual disclosure requirements for employers that sponsor defined benefit pension or other postretirement plans by removing certain requirements, providing clarification on existing requirements and adding new requirements including adding an explanation of the reasons for significant gains and losses related to changes in the benefit obligation for the period. The guidance is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2020. Early adoption is permitted. The amendments in this update are required to be applied on a retrospective basis to all periods presented. The Company is currently evaluating this guidance to determine the impact on its disclosures. In February 2018, the FASB issued ASU 2018-02, “Income Statement – Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income” which allows a reclassification from accumulated other comprehensive income to retained earnings for stranded tax effects resulting from the recent federal tax reform legislation. ASU 2018-02 eliminates the stranded tax effects resulting from the recent federal tax reform legislation and will improve the usefulness of information reported to financial statement users. The amendments in ASU 2018-02 will be applied either in the period of adoption or retrospectively to each period (or periods) in which the effect of the change in the recent federal tax reform legislation is recognized. ASU 2018-02 is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2018. Early adoption is permitted, including adoption in any interim period, for which financial statements have not yet been made available for issuance. The Company elected to early adopt ASU 2018-02 in the 2018 first quarter, which resulted in the reclassification of $7,925,000 from accumulated other comprehensive income (loss) to retained earnings due to the change in the federal corporate tax rate. In March 2017, the FASB issued ASU 2017-07, “Compensation – Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost” (“ASU 2017-07”) which requires employers to include only the service cost component of net periodic pension cost and net periodic postretirement benefit cost in operating expenses. The other components of net benefit cost are required to be presented in the income statement separately from the service cost component and outside a subtotal of income from operations. The standard allows only the service cost component to be eligible for capitalization when applicable. ASU 2017-07 is effective for annual and interim periods beginning after December 15, 2017 with early adoption permitted. This standard shall be applied retrospectively for the presentation of the service cost component and the other components of net periodic pension cost and net periodic postretirement benefit cost in the income statement and prospectively for the capitalization of the service cost benefit in assets. The Company adopted ASU 2017-07 on January 1, 2018 and applied the standard retrospectively. The other components of net benefit cost are shown in Note 11, Retirement Plans. As a result of the adoption, the Company reclassified income of $621,000 for 2017 and expense of $2,175,000 for 2016 from operating expense into non-operating expense in the condensed statement of earnings. In January 2017, the FASB issued ASU 2017-04, “Intangibles – Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment” (“ASU 2017-04”) which simplifies the subsequent measurement of goodwill by eliminating Step 2 in the goodwill impairment test that required an entity to perform procedures to determine the fair value of its assets and liabilities at the testing date. An entity instead will perform its annual, or interim, goodwill impairment test by comparing the fair value of a reporting unit with its carrying value and record an impairment charge based on the excess of a reporting unit’s carrying amount over its fair value. An entity still has the option to perform the qualitative assessment for a reporting unit to determine if the quantitative impairment test is necessary. ASU 2017-04 will be applied prospectively and is effective for annual and interim goodwill impairment tests conducted in fiscal years beginning after December 15, 2019. Early adoption is permitted for interim or annual goodwill impairment testing dates after January 1, 2017. The Company is currently evaluating the impact, if any, that the adoption of this standard will have on its consolidated financial statements. In August 2016, the FASB issued ASU 2016-15, “Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments” (“ASU 2016-15”) to create consistency in practice in how certain cash receipts and cash payments are presented and classified in the statement of cash flows. ASU 2016-15 is effective for annual and interim periods beginning after December 15, 2017. Early adoption is permitted. The Company adopted ASU 2016-15 on January 1, 2018 and the adoption of the standard did not have a material impact on the consolidated financial statements. In February 2016, the FASB issued ASU No. 2016-02, “Leases (Topic 842)” (“ASU 2016-02”) to increase transparency and comparability among organizations by requiring recognition of lease assets and lease liabilities on the balance sheet and disclosure of key information about leasing arrangements. The Company will adopt ASU 2016-02 on January 1, 2019 under the optional transition method that allows for a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption and will not restate prior periods. The Company will also elect certain practical expedients permitted under the transition guidance. While the Company is continuing to assess the potential impacts of ASU 2016-02, the Company estimates that the adoption of ASU 2016-02 will result in the recognition of right-of-use assets for operating leases of approximately $185,000,000 and lease liabilities for operating leases of approximately $180,000,000 on its Consolidated Balance Sheets, with no material impact to its Consolidated Statements of Earnings or Cash Flows. The Company does not have any financing leases as of January 1, 2019. In May 2014, the FASB issued ASU 2014-09, “Revenue from Contracts with Customers (ASC Topic 606)” (“ASU 2014-09” or “ASC 606”). ASU 2014-09 requires an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers. ASU 2014-09 replaces most existing revenue recognition guidance in United States Generally Accepted Accounting Principles and is effective for fiscal years, and interim periods within those years, beginning after December 15, 2017. ASU 2014-09 permits the use of either the retrospective, modified retrospective or prospective with a cumulative catch-up approach. The Company adopted ASU 2014-09 on January 1, 2018 under the modified retrospective approach with a cumulative adjustment that decreased the opening balance of retained earnings by $9,722,000. Prior period amounts were not adjusted and the prior period amounts continue to be reported under the accounting standards in effect for those periods. The cumulative adjustment primarily relates to recognition of revenue on certain contract manufacturing activities, primarily construction of new pressure pumping units in the Company’s distribution and services segment. The Company previously recognized revenue on manufacturing and assembly projects on a percentage of completion method using measurements of progress towards completion appropriate for the work performed. Upon the adoption of ASU 2014-09, the Company recognizes the revenues on contract manufacturing activities upon shipment and transfer of control versus the percentage of completion method. The following tables summarize the financial statement line items within the Company’s condensed consolidated financial statements impacted by ASU 2014-09 for the year ended December 31, 2018 (in thousands): 2018 As Reported Balances without Adoption of ASC 606 Effect of Change Statements of earnings: Distribution and services revenues $ 1,487,554 $ 1,515,554 $ (28,000 ) Costs of sales and operating expenses $ 2,160,946 $ 2,181,046 $ (20,100 ) Operating income $ 155,289 $ 163,189 $ (7,900 ) Earnings before taxes on income $ 114,159 $ 122,059 $ (7,900 ) Provision for taxes on income $ (35,081 ) $ (37,187 ) $ 2,106 Net earnings attributable to Kirby $ 78,452 $ 84,246 $ (5,794 ) Statements of comprehensive income: Net earnings $ 79,078 $ 84,872 $ (5,794 ) Comprehensive income attributable to Kirby $ 77,346 $ 83,140 $ (5,794 ) Statements of cash flows: Net earnings $ 79,078 $ 84,872 $ (5,794 ) Provision for deferred income taxes $ 34,881 $ 32,775 $ 2,106 Decrease in cash flows resulting from changes in: Accounts receivable $ 12,511 $ (71,624 ) $ 84,135 Inventory $ (144,685 ) $ (71,985 ) $ (72,700 ) Accrued and other liabilities $ 30,712 $ 38,459 $ (7,747 ) The following table summarizes the balance sheet line items within the Company’s condensed consolidated financial statements as of December 31, 2018 impacted by ASU 2014-09 (in thousands): December 31, 2018 As Reported Balances without Adoption of ASC 606 Effect of Change Balance sheets: Trade receivables $ 417,644 $ 501,779 $ (84,135 ) Inventories – net $ 507,441 $ 434,741 $ 72,700 Total assets $ 5,871,594 $ 5,883,029 $ (11,435 ) Deferred revenues $ 80,123 $ 70,858 $ 9,265 Deferred income taxes $ 542,785 $ 547,991 $ (5,206 ) Retained earnings $ 2,723,592 $ 2,739,086 $ (15,494 ) Total liabilities and equity $ 5,871,594 $ 5,883,029 $ (11,435 )

Revenues

Revenues	12 Months Ended
	Dec. 31, 2018
Revenues [Abstract]
Revenues	(2) Revenues The following table sets forth the Company’s revenues by major source for the years ended December 31, 2018, 2017 and 2016 (in thousands): 2018 2017 2016 Marine transportation segment: Inland transportation $ 1,119,820 $ 923,916 $ 951,097 Coastal transportation 363,323 400,190 520,796 $ 1,483,143 $ 1,324,106 $ 1,471,893 Distribution and services segment: Oil and gas $ 1,010,410 $ 614,128 $ 115,012 Commercial and industrial 477,144 276,184 183,768 $ 1,487,554 $ 890,312 $ 298,780 The Company’s revenue is measured based on consideration specified in its contracts with its customers. The Company recognizes revenue as it satisfies performance obligations in its contracts which occur as the Company delivers a service over time to its customers, or transfers control over a part or product to its customer. Marine Transportation Revenues Distribution and Services Revenues Prior to the adoption of ASU 2014-09, distribution and services manufacturing and assembly projects revenue was reported on the percentage of completion method of accounting using measurements of progress towards completion appropriate for the work performed. Upon the adoption of ASU 2014-09 on January 1, 2018, the Company recognizes the revenues on contract manufacturing activities upon shipment and transfer of control versus the percentage of completion method. Contract Assets and Liabilities Performance Obligations

Acquisitions

Acquisitions	12 Months Ended
	Dec. 31, 2018
Acquisitions [Abstract]
Acquisitions	(3) Acquisitions On December 28, 2018, the Company purchased three inland tank barges from a leasing company for $3,120,000 in cash. The Company had been leasing the barges prior to the purchase. On December 14, 2018, the Company purchased 27 inland tank barges with a barrel capacity of 306,000 barrels from CGBM 100, LLC for $28,500,000 in cash. The 27 tank barges transport petrochemicals and refined products on the Mississippi River System and the Gulf Intracoastal Waterway. The average age of the barges was eight years. On November 30, 2018, the Company purchased an inland towboat from a leasing company for $3,050,000 in cash. The Company had been leasing the towboat prior to the purchase. On May 10, 2018, the Company completed the purchase of Targa inland tank barge business from a subsidiary of Targa for $69,250,000 in cash. Targa’s inland tank barge fleet consisted of 16 pressure barges with a total capacity of 258,000 barrels, many of which were under multi-year contracts that the Company assumed from Targa. The 16 tank barges transport petrochemicals on the Mississippi River System and the Gulf Intracoastal Waterway. As a result of the acquisition, the Company recorded $16,116,000 of goodwill and $11,000,000 of intangibles with an average amortization period of 15 years. The Company expects all of the goodwill to be deductible for tax purposes. On March 15, 2018, the Company purchased two inland pressure tank barges from a competitor for $10,400,000 in cash. The average age of the two tank barges was five years. On February 14, 2018, the Company completed the acquisition of Higman for $421,922,000 in cash, subject to certain post-closing adjustments. Higman’s fleet consisted of 163 inland tank barges with 4.8 million barrels of capacity, and 75 inland towboats, transporting petrochemicals, black oil, including crude oil and natural gas condensate, and refined petroleum products on the Mississippi River System and the Gulf Intracoastal Waterway. The average age of the inland tank barges was approximately seven years and the inland towboats had an average age of approximately eight years. Financing of the acquisition was through the issuance of $500,000,000 of 4.2% senior unsecured notes due March 1, 2028 (the “2028 Notes”). The 2028 Notes were issued on February 12, 2018 in preparation for closing of the acquisition. The Company considers Higman to be a natural extension of the current marine transportation segment, expanding the capabilities of the Company’s inland based marine transportation business and lowering the average age of its inland tank barge and towboat fleet. The fair values of the assets acquired and liabilities assumed recorded at the acquisition date were as follows (in thousands): Assets: Cash $ 2,313 Accounts receivable 27,527 Prepaid expenses 5,323 Property and equipment 497,951 Goodwill 4,657 Other assets 30 Total assets $ 537,801 Liabilities: Accounts payable 17,012 Accrued liabilities 14,127 Deferred income taxes 40,524 Other long-term liabilities 44,216 Total liabilities $ 115,879 Net assets acquired $ 421,922 As a result of the acquisition, the Company recorded $4,657,000 of goodwill of which the majority will be deductible for tax purposes. The Company also incurred $11,100,000 of intangible liabilities related to unfavorable contracts with a weighted average amortization period of approximately 4.9 years. Acquisition related costs of $3,464,000, consisting primarily of legal, audit and other professional fees plus other expenses, were expensed as incurred to selling, general and administrative expense in 2018. On October 20, 2017, San Jac Marine, Inc. (“San Jac”), a subsidiary of the Company, purchased certain assets of Sneed Shipbuilding, Inc. for $14,852,000 in cash including its Channelview, Texas shipyard. San Jac is a builder of marine vessels for both inland and offshore applications as well providing repair and maintenance services. The Company intends to build towboats at the shipyard and use the facilities for routine maintenance. On September 13, 2017, the Company completed the acquisition of substantially all of the assets of Stewart & Stevenson LLC The total value of the transaction was $758,213,000 consisting of cash consideration of $377,935,000, the assumption of $13,724,000 of debt and $366,554,000 through the issuance of 5,696,259 shares of Company common stock valued at $64.35 per share, the Company’s closing share price on September 13, 2017. On June 26, 2017, in advance of the purchase of S&S, the Company entered into an amendment of its revolving credit facility that increased the borrowing limit from $550,000,000 to $850,000,000 and extended the maturity date to June 26, 2022. The debt assumed consisted of $12,135,000 of term debt and $1,589,000 of short-term secured loans related to the Company’s South American operations. The term debt was paid off without penalty in the 2017 fourth quarter. S&S, headquartered in Houston, Texas with 40 branches across 12 states, is a distributor in certain geographic areas for Allison Transmission, MTU, Detroit Diesel, EMD Power Products (“EMD”), Deutz and several other manufacturers. S&S’ principal customers are oilfield service companies, oil and gas operators and producers, and companies in the marine, mining, power generation, on-highway and other commercial and industrial applications. On July 10, 2017, the Company completed the purchase of certain inland marine assets from an undisclosed competitor for $68,000,000 in cash. The assets purchased consisted of nine specialty pressure tank barges, four 30,000 barrel tank barges and three 1320 horsepower inland towboats. The average age of the 13 inland tank barges was five years. The 13 tank barges transport petrochemicals and refined petroleum products on the Mississippi River System and the Gulf Intracoastal Waterway. As a result of the acquisition, the Company recorded $67,970,000 of property and $30,000 of intangibles with a weighted average amortization period of two years. During July 2017, the Company purchased four inland tank barges for $1,450,000 as well as a barge fleeting and marine fueling operation business in Freeport, Texas for $3,900,000. The Company had been leasing the barges prior to the purchase. On October 11, 2016, the Company purchased certain assets of Valley Power Systems, Inc. and Valley Power Systems Northwest, Inc. (collectively “VPS”) for $11,440,000 in cash. The assets purchased are mainly related to the EMD engine supply and repair business of VPS and include an EMD distributor agreement to sell engines in nine western states. As a result of the acquisition, the Company recorded $8,330,000 of goodwill and $2,070,000 of intangibles with a weighted average amortization period of approximately 15 years. The Company expects all of the goodwill to be deductible for tax purposes. On June 30, 2016, the Company purchased an 80,000 barrel coastal tank barge from TD Equipment Finance, Inc. (“TD Equipment”) for $13,682,000 in cash. The Company had been leasing the barge from TD Equipment prior to its purchase. On June 2, 2016, the Company purchased four coastal tugboats from Crosby Marine Transportation LLC for $26,450,000 in cash. The four coastal tugboats have an average age of 13 years. On April 15, 2016, the Company purchased the inland tank barge fleet of SEACOR Holdings Inc. (“Seacor”) from subsidiaries of Seacor for a total value of $89,181,000. The assets purchased consisted of 27 inland 30,000 barrel tank barges and 14 inland towboats. The purchase price was comprised of $85,500,000 in cash and the transfer to Seacor of a Florida-based ship docking tugboat with a value of $3,681,000. The average age of the 27 inland tank barges was ten years. Seacor, through its subsidiary, SCF Waxler Marine LLC, transported refined petroleum products, petrochemicals and black oil on the Mississippi River System and the Gulf Intracoastal Waterway. As a result of the acquisition, the Company recorded $985,000 of goodwill and expects all of the goodwill to be deductible for tax purposes. No intangibles other than goodwill were identified in the acquisition. The following unaudited pro forma results present consolidated information as if the S&S acquisition had been completed as of January 1, 2016. The pro forma results do not include any of the other acquisitions completed in 2016 through 2018 described above as the effect of these acquisitions would not be materially different from the Company’s actual results. The pro forma results include the amortization associated with the acquired intangible assets, interest expense associated with the debt used to fund a portion of the acquisition, the impact of the additional shares issued in connection with the S&S acquisition, removal of a product line sold in 2016 and the impact of certain fair value adjustments such as depreciation adjustments related to adjustments to property and equipment. The pro forma results do not include any cost savings or potential synergies related to the acquisition nor any integration costs. The pro forma results should not be considered indicative of the results of operations or financial position of the combined companies had the acquisitions had been consummated as of January 1, 2016 and are not necessarily indicative of results of future operations of the Company. The following table sets forth the Company’s pro forma revenues and net earnings attributable to Kirby for the years ended December 31, 2016 and 2017 (unaudited and in thousands): 2016 Pro forma 2017 Pro forma Revenues $ 2,299,800 $ 2,556,131 Net earnings attributable to Kirby $ 125,197 $ 303,097

Impairment of Long-lived Assets

Impairment of Long-lived Assets	12 Months Ended
	Dec. 31, 2018
Impairment of Long-lived Assets [Abstract]
Impairment of Long-lived Assets	(4) Impairment of Long-lived Assets During the fourth quarter of 2018, the Company recorded a $82,705,000 non-cash pre-tax impairment charge. The after-tax effect of the charge was $65,337,000 or $1.09 per share. The USCG adopted regulations on ballast water management systems (“BWMS”) establishing a standard for the allowable concentration of living organisms in certain vessel ballast water discharged in waters of the United States under the National Invasive Species Act. The regulations include requirements for the installation of engineering equipment to treat ballast water by establishing an approval process for BWMS. The USCG has approved manufacturers’ systems that met the regulatory discharge standard equivalent to the International Maritime Organization’s D-2 standard. The phase-in schedule for those existing vessels requiring a system to install BWMS equipment is dependent on vessel build date, ballast water capacity, and drydock schedule. Compliance with the ballast water treatment regulations requires the installation of equipment on some of the Company’s vessels to treat ballast water before it is discharged. The installation of BWMS equipment will require significant capital expenditures at the next scheduled drydocking to complete the installation of the approved system on those existing vessels that require a system to complay with the BWMS regulations. Due to the advanced age of four of the Company’s older articulated tank barge and tugboat units (“ATBs”) and the high cost of installation of BWMS, the Company will retire the ATBs at their next scheduled shipyard dates which range between 2020 and 2023 instead of installing the expensive BWMS equipment required to operate the vessels past their next required shipyard dates. A pre-tax impairment charge of $78,835,000 was incurred in the fourth quarter of 2018 to reduce the ATBs to a fair value of $13,247,000 due to reduced estimated cash flows resulting from reduced lives on these four older ATBs. The reduced estimated useful lives are due to the assessment of the impact of the new regulations by USCG that require the installation of BWMS. The fair value of the four ATBs of $13,247,000 is presented in marine transportation equipment at December 31, 2018. The impairment charge also included a pre-tax charge of $3,870,000 as the Company reduced the carrying value of its improvements in a leased barge to its scrap value of $220,000. As part of a lease termination, the Company agreed to terminate the lease, purchase the barge and then scrap the barge which resulted in the Company committing to put the barge up for sale in December 2018. The barge was scrapped in January 2019. The fair market value of the barge was $220,000 at December 31, 2018, and was presented in prepaid expenses and other current assets. In addition, the Company incurred $2,403,000 in lease cancellation costs in December 2018 related to the leased barge. During the fourth quarter of 2017, the Company recorded a $105,712,000 non-cash pre-tax impairment charge. The after-tax effect of the charge was $66,975,000 or $1.20 per share. The impairment charge was to reduce certain vessels to a fair value of $12,550,000 as the Company decided to put certain older out-of-service vessels up for sale in its marine transportation segment in response to lower equipment utilization, pricing pressure and expensive BWMS installations required in the next few years on some of the coastal tank barges. Retiring some of the older coastal marine vessels reduces the fleet’s age profile and improves the efficiency of the fleet. The fair market value of the vessels was $12,550,000 at December 31, 2017, and was presented in prepaid expenses and other current assets.

Inventories

Inventories	12 Months Ended
	Dec. 31, 2018
Inventories [Abstract]
Inventories	(5) Inventories The following table presents the details of inventories as of December 31, 2018 and 2017 (in thousands): December 31, 2018 December 31, 2017 Finished goods $ 406,364 $ 242,333 Work in process 101,077 73,396 $ 507,441 $ 315,729

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2018
Fair Value Measurements [Abstract]
Fair Value Measurements	(6) Fair Value Measurements The accounting guidance for using fair value to measure certain assets and liabilities establishes a three tier value hierarchy, which prioritizes the inputs to valuation techniques used in measuring fair value. These tiers include: Level 1, defined as observable inputs such as quoted prices in active markets for identical assets or liabilities; Level 2, defined as inputs other than quoted prices in active markets that are either directly or indirectly observable; and Level 3, defined as unobservable inputs in which little, if any, market data exists, therefore requiring an entity to develop its own assumptions about the assumptions that market participants would use in pricing the asset or liability. Cash and cash equivalents, accounts receivable, accounts payable and accrued liabilities have carrying values that approximate fair value due to the short-term maturity of these financial instruments. The fair value of the Company’s debt instruments is described in Note 7, Long-Term Debt. Certain assets are measured at fair value on a nonrecurring basis. These assets are adjusted to fair value when there is evidence of impairment. During the 2018 fourth quarter, the Company reduced certain vessels to fair value due to its decision in 2018 to retire certain older vessels requiring expensive BWMS equipment at their next scheduled drydock and put a certain older barge up for sale in its marine transportation segment. The fair value of these vessels was $13,467,000 at December 31, 2018 and $13,247,000 is presented in marine transportation equipment and $220,000 is presented in prepaid expenses and other current assets.

Long-Term Debt

Long-Term Debt	12 Months Ended
	Dec. 31, 2018
Long-Term Debt [Abstract]
Long-Term Debt	(7) Long-Term Debt Long-term debt at December 31, 2018 and 2017 consisted of the following (in thousands): 2018 2017 Long-term debt, including current portion: $850,000,000 revolving credit facility due June 26, 2022 $ 417,373 $ 495,845 $150,000,000 senior notes Series A due February 27, 2020 150,000 150,000 $350,000,000 senior notes Series B due February 27, 2023 350,000 350,000 $500,000,000 senior notes due March 1, 2028 500,000 — $10,000,000 credit line due June 30, 2019 — — Bank notes payable 19 3 1,417,392 995,848 Unamortized debt issuance costs (6,550 ) (3,442 ) Unamortized debt discount (654 ) — $ 1,410,188 $ 992,406 The aggregate payments due on the long-term debt in each of the next five years were as follows (in thousands): 2019 $ 19 2020 150,000 2021 — 2022 417,373 2023 350,000 Thereafter 500,000 $ 1,417,392 On February 12, 2018, the Company issued $500,000,000 of 4.2% senior unsecured notes due March 1, 2028 (the “2028 Notes”) with U.S. Bank National Association, as trustee. Interest payments of $10,500,000 are due semi-annually on March 1 and September 1 of each year, with the exception of the first payment on September 1, 2018, which was $11,608,000. The Company received cash proceeds of $495,019,000, net of the original issue discount of $705,000 and debt issuance costs of $4,276,000. The 2028 Notes are unsecured and rank equally in right of payment with the Company’s other unsecured senior indebtedness. The 2028 Notes contain certain covenants on the part of the Company, including covenants relating to liens, sale-leasebacks, asset sales and mergers, among others. The 2028 Notes also specify certain events of default, upon the occurrence of which the maturity of the notes may be accelerated, including failure to pay principal and interest, violation of covenants or default on other indebtedness, among others. The Company used the proceeds from the issuance of the 2028 Notes to fund the acquisition of Higman. The remaining net proceeds of the sale of the 2028 Notes were used for the repayment of indebtedness under the Company’s bank credit facilities. As of December 31, 2018, the Company was in compliance with all the 2028 Notes covenants and had $500,000,000 outstanding under the 2028 Notes. The Company has an $850,000,000 unsecured revolving credit facility (“Revolving Credit Facility”) with a syndicate of banks, with JPMorgan Chase Bank, N.A. as the administrative agent bank, with a maturity date of June 26, 2022. In addition, the credit agreement allows for a $300,000,000 increase in the aggregate commitments of the banks in the form of revolving credit loans or term loans, subject to the consent of each bank that elects to participate in the increased commitment. The variable interest rate spread varies with the Company’s senior debt rating and, effective February 20, 2018, due to a change in one of the Company’s credit ratings, the spread over LIBOR increased from 1.00% to 1.125% and the Alternate Base Rate spread is currently 0.125% over the agent bank’s prime rate. The commitment fee increased as well from 0.10% to 0.15%. The Revolving Credit Facility contains certain restrictive financial covenants including an interest coverage ratio and a debt-to-capitalization ratio. In addition to financial covenants, the Revolving Credit Facility contains covenants that, subject to exceptions, restrict debt incurrence, mergers and acquisitions, sales of assets, dividends and investments, liquidations and dissolutions, capital leases, transactions with affiliates and changes in lines of business. Borrowings under the Revolving Credit Facility may be used for general corporate purposes, the purchase of existing or new equipment, the purchase of the Company’s common stock, or for business acquisitions. As of December 31, 2018, the Company was in compliance with all Revolving Credit Facility covenants and had $417,373,000 of debt outstanding under the Revolving Credit Facility. The average borrowing under the Revolving Credit Facility during 2018 was $411,613,000, computed by averaging the daily balance, and the weighted average interest rate was 3.1%, computed by dividing the interest expense under the Revolving Credit Facility by the average Revolving Credit Facility borrowing. The Revolving Credit Facility includes a $25,000,000 commitment which may be used for standby letters of credit. Outstanding letters of credit under the Revolving Credit Facility were $6,788,000 as of December 31, 2018. The Company has $500,000,000 of unsecured senior notes (“Senior Notes Series A” and “Senior Notes Series B”) with a group of institutional investors, consisting of $150,000,000 of 2.72% Senior Notes Series A due February 27, 2020 and $350,000,000 of 3.29% Senior Notes Series B due February 27, 2023. No principal payments are required until maturity. The Senior Notes Series A and Series B contain certain covenants on the part of the Company, including an interest coverage covenant, a debt-to-capitalization covenant and covenants relating to liens, asset sales and mergers, among others. The Senior Notes Series A and Series B also specify certain events of default, upon the occurrence of which the maturity of the notes may be accelerated, including failure to pay principal and interest, violation of covenants or default on other indebtedness, among others. As of December 31, 2018, the Company was in compliance with all Senior Notes Series A and Series B covenants and had $150,000,000 of Senior Notes Series A outstanding and $350,000,000 of Senior Notes Series B outstanding. The Company has a $10,000,000 line of credit (“Credit Line”) with Bank of America, N.A. (“Bank of America”) for short-term liquidity needs and letters of credit, with a maturity date of June 30, 2019. The Credit Line allows the Company to borrow at an interest rate agreed to by Bank of America and the Company at the time each borrowing is made or continued. The Company had no borrowings outstanding under the Credit Line as of December 31, 2018. Outstanding letters of credit under the Credit Line were $1,171,000 as of December 31, 2018. On September 13, 2017, as a result of the S&S acquisition, the Company assumed $12,135,000 of term debt which was paid off without penalty in the 2017 fourth quarter. The Company also had $19,000 of short-term secured loans outstanding, as of December 31, 2018, related to its South American operations. The estimated fair value of total debt outstanding at December 31, 2018 and 2017 was $1,411,628,000 and $984,017,000, respectively, which differs from the carrying amount of $1,410,188,000 and $992,406,000, respectively, included in the consolidated financial statements. The fair value was determined using an income approach that relies on inputs such as yield curves.

Taxes on Income

Taxes on Income	12 Months Ended
	Dec. 31, 2018
Taxes on Income [Abstract]
Taxes on Income	(8) Taxes on Income Earnings before taxes on income and details of the provision for taxes on income for the years ended December 31, 2018, 2017 and 2016 were as follows (in thousands): 2018 2017 2016 Earnings (loss) before taxes on income: United States $ 117,800 $ 74,267 $ 227,746 Foreign (3,641 ) (1,253 ) — $ 114,159 $ 73,014 $ 227,746 Provision (benefit) for taxes on income: U.S. Federal: Current $ — $ 11,143 $ 28,919 Deferred 27,102 (258,703 ) 49,685 $ 27,102 $ (247,560 ) $ 78,604 U.S. State: Current $ (243 ) $ 3,861 $ 4,727 Deferred 7,619 2,280 1,611 $ 7,376 $ 6,141 $ 6,338 Foreign: Current $ 443 $ 370 $ — Deferred 160 160 — $ 603 $ 530 $ — Consolidated: Current $ 200 $ 15,374 $ 33,646 Deferred 34,881 (256,263 ) 51,296 $ 35,081 $ (240,889 ) $ 84,942 In 2018, the Company filed its 2017 US tax return and completed its analysis of the income tax impacts of the Tax Cuts and Jobs Act which was signed into law on December 22, 2017. There are no material changes to the income tax effects to those previously reported in 2017. The Company’s provision for taxes on income varied from the statutory federal income tax rate for the years ended December 31, 2018, 2017 and 2016 due to the following: 2018 2017 2016 United States income tax statutory rate 21.0 % 35.0 % 35.0 % State and local taxes, net of federal benefit 6.5 0.9 1.8 Change due to U.S. tax reform — (369.0 ) — Other – net 3.2 3.2 0.5 30.7 % (329.9 )% 37.3 % The tax effects of temporary differences that give rise to significant portions of the non-current deferred tax assets and liabilities at December 31, 2018 and 2017 were as follows (in thousands): 2018 2017 Non-current deferred tax assets and liabilities: Deferred tax assets: Allowance for doubtful accounts $ 2,105 $ 1,875 Inventory 5,017 3,795 Insurance accruals 4,119 4,599 Deferred compensation 1,291 1,849 Unrealized loss on defined benefit plans 9,891 11,097 Operating loss carryforwards 81,867 15,540 Pension benefits 6,559 549 Other 22,421 16,301 133,270 55,605 Valuation allowances (25,568 ) (15,308 ) 107,702 40,297 Deferred tax liabilities: Property (526,873 ) (428,947 ) Deferred state taxes (74,638 ) (58,366 ) Goodwill and other intangibles (34,235 ) (9,015 ) Other (14,741 ) (12,420 ) (650,487 ) (508,748 ) $ (542,785 ) $ (468,451 ) During 2018, the Company generated a net operating loss mainly caused by taking the full cost deduction of purchased fixed assets. The deferred tax assets of $18,922,000 has been recorded at December 31, 2018 and can be utilized by future taxable income indefinitely. The Company also inherited a $35,133,000 historical net operating loss of Higman, which was acquired in February 2018 and more fully described in Note 3, Acquisitions. The Higman loss will expire in various amounts through 2037. After conducting loss utilization limit and future gain recognition research, the Company has determined that it is more likely than not that all federal deferred tax assets at December 31, 2018 will be realized. The Company had state operating loss deferred tax assets of $19,039,000 in 2018 and $9,289,000 in 2017. The valuation allowance for state deferred tax assets as of December 31, 2018 and 2017 was $17,027,000 and $9,289,000, respectively, related to the Company’s state net operating loss carryforwards based on the Company’s determination that it is more likely than not that the deferred tax assets will not be realized. Expiration of these state net operating loss carryforwards vary by state through 2037 and none will expire in fiscal 2019. As of December 31, 2018, the Company had a Canadian net operating loss carryforward of $8,541,000 which expires in 2038. A full valuation allowance has been provided for this asset. The Company or one of its subsidiaries files income tax returns in the United States federal jurisdiction and various state jurisdictions. The Company is currently open to audit under the statute of limitations by the Internal Revenue Service for the 2015 through 2017 tax years. With few exceptions, the Company and its subsidiaries’ state income tax returns are open to audit under the statute of limitations for the 2012 through 2017 tax years. As of December 31, 2018, the Company has provided a liability of $1,909,000 for unrecognized tax benefits related to various income tax issues which includes interest and penalties. The amount that would impact the Company’s effective tax rate, if recognized, is $1,182,000, with the difference between the total amount of unrecognized tax benefits and the amount that would impact the effective tax rate being primarily related to the federal tax benefit of state income tax items. It is not reasonably possible to determine if the liability for unrecognized tax benefits will significantly change prior to December 31, 2019 due to the uncertainty of possible examination results. A reconciliation of the beginning and ending amount of the liability for unrecognized tax benefits for the years ended December 31, 2018, 2017 and 2016, is as follows (in thousands): 2018 2017 2016 Balance at beginning of year $ 1,787 $ 2,019 $ 1,958 Additions based on tax positions related to the current year 254 403 187 Additions for tax positions of prior years 70 273 867 Reductions for tax positions of prior years (668 ) (908 ) (441 ) Settlements — — (552 ) Balance at end of year $ 1,443 $ 1,787 $ 2,019 The Company accounts for interest and penalties related to uncertain tax positions as part of its provision for federal and state income taxes. The Company recognized net benefit of $209,000 in interest and penalties for the year ended December 31, 2018 and net expense of $120,000 and $88,000 in interest and penalties for the years ended December 31, 2017 and 2016, respectively. The Company had $466,000, $675,000 and $554,000 of accrued liabilities for the payment of interest and penalties at December 31, 2018, 2017 and 2016, respectively.

Leases

Leases	12 Months Ended
	Dec. 31, 2018
Leases [Abstract]
Leases	(9) Leases The Company and its subsidiaries currently lease various facilities and equipment under a number of cancelable and noncancelable operating leases. Lease agreements for barges have terms from one to 12 years expiring at various dates through 2028. Lease agreements for towing vessels chartered by the Company have terms from 30 days to ten years expiring at various dates through 2027; however, approximately 75% of the towing vessel charter agreements are for terms of one year or less. Total rental expense for the years ended December 31, 2018, 2017 and 2016 was as follows (in thousands): 2018 2017 2016 Rental expense: Marine equipment — barges $ 10,234 $ 11,550 $ 13,791 Marine equipment — towing vessels 140,389 116,690 137,609 Other buildings and equipment 23,365 15,915 11,182 Rental expense $ 173,988 $ 144,155 $ 162,582 Future minimum lease payments under operating leases that have initial or remaining noncancelable lease terms in excess of one year at December 31, 2018 were as follows (in thousands): Land, Buildings Marine Equipment And Equipment Barges Towing Vessels Total 2019 $ 19,524 $ 6,808 $ 70,759 $ 97,091 2020 16,916 5,400 7,746 30,062 2021 15,112 4,128 2,578 21,818 2022 13,547 4,138 2,578 20,263 2023 11,821 3,030 2,578 17,429 Thereafter 75,818 7,098 9,023 91,939 $ 152,738 $ 30,602 $ 95,262 $ 278,602

Stock Award Plans

Stock Award Plans	12 Months Ended
	Dec. 31, 2018
Stock Award Plans [Abstract]
Stock Award Plans	(10) Stock Award Plans The Company has share-based compensation plans which are described below. The compensation cost that has been charged against earnings for the Company’s stock award plans and the income tax benefit recognized in the statement of earnings for stock awards for the years ended December 31, 2018, 2017 and 2016 were as follows (in thousands): 2018 2017 2016 Compensation cost $ 19,104 $ 11,460 $ 11,675 Income tax benefit $ 5,903 $ 4,333 $ 4,378 The Company has an employee stock award plan for selected officers and other key employees which provides for the issuance of stock options, restricted stock awards and performance awards. On February 19, 2018, the employee stock award plan was amended to also allow for the granting of RSUs to selected officers and other key employees. The amendment included a provision for the continued vesting of unvested stock options and RSUs for employees who meet certain years of service and age requirements at the time of their retirement. The vesting change resulted in shorter expense accrual periods on stock options and RSUs granted after February 19, 2018 to employees who are nearing retirement and meet the service and age requirements. The exercise price for each option equals the fair market value per share of the Company’s common stock on the date of grant. Substantially all stock options outstanding under the plan have terms of seven years and vest ratably over three years. No performance awards payable in stock have been awarded under the plan. At December 31, 2018, 1,575,948 shares were available for future grants under the employee plan and no outstanding stock options under the employee plan were issued with stock appreciation rights. The following is a summary of the stock option activity under the employee plan described above for the years ended December 31, 2018, 2017 and 2016: Outstanding Non- Qualified or Nonincentive Stock Awards Weighted Average Exercise Price Outstanding at December 31, 2015 430,432 $ 71.01 Granted 186,706 $ 53.50 Canceled or expired (16,017 ) $ 80.17 Outstanding at December 31, 2016 601,121 $ 65.33 Granted 123,141 $ 68.46 Exercised (36,616 ) $ 47.95 Canceled or expired (32,991 ) $ 74.07 Outstanding at December 31, 2017 654,655 $ 66.45 Granted 115,797 $ 75.50 Exercised (283,886 ) $ 61.81 Canceled or expired (21,864 ) $ 102.42 Outstanding at December 31, 2018 464,702 $ 69.85 Under the employee plan, stock options exercisable were 230,254, 380,608 and 321,942 at December 31, 2018, 2017 and 2016, respectively. The following table summarizes information about the Company’s outstanding and exercisable stock options under the employee plan at December 31, 2018: Options Outstanding Options Exercisable Range of Exercise Prices Number Outstanding Weighted Average Remaining Contractual Life in Years Weighted Average Exercise Price Aggregated Intrinsic Value Number Exercisable Weighted Average Exercise Price Aggregated Intrinsic Value $51.23 90,975 4.1 $ 51.23 57,438 $ 51.23 $64.65 – $68.50 126,260 4.7 $ 67.23 41,146 $ 67.40 $70.65 – $75.50 207,156 4.5 $ 74.56 91,359 $ 73.36 $93.64 – $101.46 40,311 2.1 $ 95.90 40,311 $ 95.90 $51.23 – $101.46 464,702 4.3 $ 69.85 $1,570,000 230,254 $ 70.72 $951,000 The following is a summary of the restricted stock award activity under the employee plan described above for the years ended December 31, 2018, 2017 and 2016: Unvested Restricted Stock Award Shares Weighted Average Grant Date Fair Value Per Share Nonvested balance at December 31, 2015 311,727 $ 75.73 Granted 190,610 $ 53.56 Vested (105,109 ) $ 69.93 Forfeited (19,573 ) $ 76.06 Nonvested balance at December 31, 2016 377,655 $ 66.14 Granted 127,255 $ 68.50 Vested (105,600 ) $ 68.91 Forfeited (35,189 ) $ 69.45 Nonvested balance at December 31, 2017 364,121 $ 65.84 Vested (144,265 ) $ 72.66 Forfeited (5,640 ) $ 64.60 Nonvested balance at December 31, 2018 214,216 $ 64.73 The following is a summary of RSU activity under the employee plan described above for the year ended December 31, 2018: Unvested RSUs Weighted Average Grant Date Fair Value Per Unit Nonvested balance at December 31, 2017 — $ — Granted 143,890 $ 75.59 Forfeited (2,835 ) $ 75.50 Nonvested balance at December 31, 2018 141,055 $ 75.59 The Company has a stock award plan for nonemployee directors of the Company which provides for the issuance of stock options and restricted stock. The director plan provides for automatic grants of restricted stock to nonemployee directors after each annual meeting of stockholders. In addition, the director plan allows for the issuance of stock options or restricted stock in lieu of cash for all or part of the annual director fee at the option of the director. The exercise prices for all options granted under the plan are equal to the fair market value per share of the Company’s common stock on the date of grant. The terms of the options are ten years. The restricted stock issued after each annual meeting of stockholders vests six months after the date of grant. Options granted and restricted stock issued in lieu of cash director fees vest in equal quarterly increments during the year to which they relate. At December 31, 2018, 486,058 shares were available for future grants under the director plan. The director stock award plan is intended as an incentive to attract and retain qualified independent directors. The following is a summary of the stock option activity under the director plan described above for the years ended December 31, 2018, 2017, and 2016: Outstanding Non- Qualified or Nonincentive Stock Awards Weighted Average Exercise Price Outstanding at December 31, 2015 220,429 $ 64.37 Exercised (9,000 ) $ 35.72 Canceled or expired (6,000 ) $ 99.52 Outstanding at December 31, 2016 205,429 $ 64.60 Granted 3,188 $ 70.65 Exercised (39,000 ) $ 46.23 Canceled or expired (12,000 ) $ 87.35 Outstanding at December 31, 2017 157,617 $ 67.54 Granted 2,640 $ 85.30 Exercised (29,153 ) $ 57.47 Outstanding at December 31, 2018 131,104 $ 70.14 Under the director plan, options exercisable were 130,444, 156,820 and 205,429 at December 31, 2018, 2017 and 2016, respectively. The following table summarizes information about the Company’s outstanding and exercisable stock options under the director plan at December 31, 2018: Options Outstanding Options Exercisable Range of Exercise Prices Number Outstanding Weighted Average Remaining Contractual Life in Years Weighted Average Exercise Price Aggregate Intrinsic Value Number Exercisable Weighted Average Exercise Price Aggregate Intrinsic Value $29.60 6,000 0.3 $ 29.60 6,000 $ 29.60 $41.24 – $56.45 31,276 1.9 $ 50.61 31,276 $ 50.61 $61.89 – $62.48 28,000 3.6 $ 62.27 28,000 $ 62.27 $70.65 – $99.52 65,828 5.2 $ 86.45 65,168 $ 86.47 $29.60 – $99.52 131,104 3.8 $ 70.14 $893,000 130,444 $ 70.06 $893,000 The following is a summary of the restricted stock award activity under the director plan described above for the years ended December 31, 2018, 2017 and 2016: Unvested Restricted Stock Award Shares Weighted Average Grant Date Fair Value Per Share Nonvested balance at December 31, 2015 1,791 $ 68.73 Granted 23,074 $ 64.89 Vested (24,518 ) $ 65.17 Nonvested balance at December 31, 2016 347 $ 64.89 Granted 21,198 $ 70.65 Vested (21,226 ) $ 70.56 Nonvested balance at December 31, 2017 319 $ 70.65 Granted 21,373 $ 85.70 Vested (21,428 ) $ 85.48 Nonvested balance at December 31, 2018 264 $ 85.30 The total intrinsic value of all stock options exercised under all of the Company’s plans was $6,709,000, $1,671,000 and $266,000 for the years ended December 31, 2018, 2017 and 2016, respectively. The actual tax benefit realized for tax deductions from stock option exercises was $2,073,000, $632,000 and $100,000 for the years ended December 31, 2018, 2017 and 2016, respectively. The total intrinsic value of all the restricted stock vestings under all of the Company’s plans was $12,936,000, $8,485,000 and $6,928,000 for the years ended December 31, 2018, 2017 and 2016, respectively. The actual tax benefit realized for tax deductions from restricted stock vestings was $3,997,000, $3,208,000 and $2,598,000 for the years ended December 31, 2018, 2017 and 2016, respectively. There were no RSU vestings for the year ended December 31, 2018. As of December 31, 2018, there was $2,294,000 of unrecognized compensation cost related to nonvested stock options, $8,647,000 related to restricted stock and $5,732,000 related to nonvested RSUs. The stock options are expected to be recognized over a weighted average period of approximately 1.5 years, restricted stock over approximately 2.2 years and RSUs over approximately 3.9 years. The total fair value of stock options vested was $3,191,000, $2,530,000 and $2,495,000 during the years ended December 31, 2018, 2017 and 2016, respectively. The fair value of the restricted stock vested was $12,936,000, $8,485,000 and $6,928,000 for the years ended December 31, 2018, 2017 and 2016, respectively. The weighted average per share fair value of stock options granted during the years ended December 31, 2018, 2017 and 2016 was $23.53, $20.72 and $17.30, respectively. The fair value of the stock options granted during the years ended December 31, 2018, 2017 and 2016 was $2,787,000, $2,617,000 and $3,231,000, respectively. The Company currently uses treasury stock shares for restricted stock grants and stock option exercises. The fair value of each stock option was determined using the Black-Scholes option pricing model. The key input variables used in valuing the stock options during the years ended December 31, 2018, 2017 and 2016 were as follows: 2018 2017 2016 Dividend yield None None None Average risk-free interest rate 2.7 % 2.0 % 1.5 % Stock price volatility 27 % 27 % 30 % Estimated option term Six years Six years Six years

Retirement Plans

Retirement Plans	12 Months Ended
	Dec. 31, 2018
Retirement Plans [Abstract]
Retirement Plans	(11) Retirement Plans The Company sponsors a defined benefit plan for its inland vessel personnel and shore based tankermen. The plan benefits are based on an employee’s years of service and compensation. The plan assets consist primarily of equity and fixed income securities. On April 12, 2017, the Company amended its pension plan to cease all benefit accruals for periods after May 31, 2017 for certain participants. Participants grandfathered and not impacted were those, as of the close of business on May 31, 2017, who either (a) had completed 15 years of pension service or (b) had attained age 50 and completed 10 years of pension service. Participants non-grandfathered are eligible to receive discretionary 401(k) plan contributions. The Company did not incur any one-time charges related to this amendment but the pension plan’s projected benefit obligation decreased by $33,433,000. On February 14, 2018, with the acquisition of Higman, the Company assumed Higman’s pension plan for its inland vessel personnel and office staff. On March 27, 2018, the Company amended the Higman pension plan to close it to all new entrants and cease all benefit accruals for periods after May 15, 2018 for all participants. The Company did not incur any one-time charges related to this amendment but the Higman pension plan’s projected benefit obligation decreased by $3,081,000. The Company made a pension contribution to the Higman plan of $6,717,000 in March 2018 to complete all required funding for the 2016 and 2017 years and make its 2018 first quarter contribution. The Company made an additional contribution to the Higman pension plan of $1,385,000 in the fourth quarter of 2018 for the 2018 year. The fair value of plan assets of the Company’s pension plans was $303,151,000 and $294,995,000 at December 31, 2018 and 2017 respectively. As of December 31, 2018 and 2017, these assets were allocated among asset categories as follows: Asset Category 2018 2017 Current Minimum, Target and Maximum Allocation Policy U.S. equity securities 52 % 51 % 30% — 50%— 70 % International equity securities 17 % 21 % 0% — 20%— 30 % Debt securities 28 % 28 % 15% — 30%— 55 % Cash and cash equivalents 3 % — % 0% — 0%— 5 % 100 % 100 % The plan assets are invested entirely in common collective trusts. These instruments are public investment vehicles valued using the net asset value provided by the administrator of the fund. The net asset value is classified within Level 2 of the valuation hierarchy as set forth in the accounting guidance for fair value measurements because the net asset value price is quoted on an inactive private market although the underlying investments are traded on an active market. The Company’s investment strategy focuses on total return on invested assets (capital appreciation plus dividend and interest income). The primary objective in the investment management of assets is to achieve long-term growth of principal while avoiding excessive risk. Risk is managed through diversification of investments within and among asset classes, as well as by choosing securities that have an established trading and underlying operating history. The Company makes various assumptions when determining defined benefit plan costs including, but not limited to, the current discount rate and the expected long-term return on plan assets. Discount rates are determined annually and are based on a yield curve that consists of a hypothetical portfolio of high quality corporate bonds with maturities matching the projected benefit cash flows. The Company assumed that plan assets would generate a long-term rate of return of 7.0% in 2018 and 2017. The Company developed its expected long-term rate of return assumption by evaluating input from investment consultants comparing historical returns for various asset classes with its actual and targeted plan investments. The Company believes that its long-term asset allocation, on average, will approximate the targeted allocation. The Company’s pension plan funding strategy is to make annual contributions in amounts equal to or greater than amounts necessary to meet minimum government funding requirements. The plan’s benefit obligations are based on a variety of demographic and economic assumptions, and the pension plan assets’ returns are subject to various risks, including market and interest rate risk, making an accurate prediction of the pension plan contribution difficult. The Company’s pension plan funding was 85% of the pension plans’ ABO at December 31, 2018, including the Higman pension plan. The Company sponsors an unfunded defined benefit health care plan that provides limited postretirement medical benefits to employees who met minimum age and service requirements, and to eligible dependents. The plan limits cost increases in the Company’s contribution to 4% per year. The plan is contributory, with retiree contributions adjusted annually. The plan eliminated coverage for future retirees as of December 31, 2011. The Company also has an unfunded defined benefit supplemental executive retirement plan (“SERP”) that was assumed in an acquisition in 1999. That plan ceased to accrue additional benefits effective January 1, 2000. The following table presents the change in benefit obligation and plan assets for the Company’s defined benefit plans and postretirement benefit plan (in thousands): Other Postretirement Benefits Pension Benefits Postretirement Welfare Plan Pension Plan SERP 2018 2017 2018 2017 2018 2017 Change in benefit obligation Benefit obligation at beginning of year $ 354,994 $ 337,176 $ 1,412 $ 1,457 $ 679 $ 675 Service cost 7,622 10,677 — — — — Interest cost 15,499 13,729 49 58 24 27 Actuarial loss (gain) (44,935 ) 34,563 (70 ) 42 143 52 Gross benefits paid (11,749 ) (7,718 ) (145 ) (145 ) (103 ) (75 ) Curtailments (3,081 ) (33,433 ) — — — — Acquisition 63,133 — — — — — Benefit obligation at end of year $ 381,483 $ 354,994 $ 1,246 $ 1,412 $ 743 $ 679 Accumulated benefit obligation at end of year $ 356,797 $ 324,904 $ 1,246 $ 1,412 $ 743 $ 679 Weighted-average assumption used to determine benefit obligation at end of year Discount rate (a) 4.4 % 3.7 % 4.4 % 3.7 % 4.4 % 3.7 % Rate of compensation increase Service-based table Service-based table — — — — Health care cost trend rate Initial rate — — — — 7.0 % 7.0 % Ultimate rate — — — — 5.0 % 5.0 % Years to ultimate — — — — 2025 2022 Effect of one-percentage-point change in assumed health care cost trend rate on postretirement obligation Increase $ — $ — $ — $ — $ 75 $ 75 Decrease — — — — (65 ) (65 ) Change in plan assets Fair value of plan assets at beginning of year $ 294,995 $ 257,517 $ — $ — $ — $ — Actual return on plan assets (18,214 ) 45,196 — — — — Employer contribution 8,102 — 145 145 103 75 Gross benefits paid (11,749 ) (7,718 ) (145 ) (145 ) (103 ) (75 ) Acquisition 30,017 — — — — — Fair value of plan assets at end of year $ 303,151 $ 294,995 $ — $ — $ — $ — (a) The discount rate for the Higman pension plan in 2018 was changed from 4.13% as of February 14, 2018 and 4.02% as of March 31, 2018 to 4.40% as of December 31, 2018. The following table presents the funded status and amounts recognized in the Company’s consolidated balance sheet for the Company’s defined benefit plans and postretirement benefit plan at December 31, 2018 and 2017 (in thousands): Other Postretirement Benefits Pension Benefits Postretirement Welfare Plan Pension Plan SERP 2018 2017 2018 2017 2018 2017 Funded status at end of year Fair value of plan assets $ 303,151 $ 294,995 $ — $ — $ — $ — Benefit obligations (381,483 ) (354,994 ) (1,246 ) (1,412 ) (743 ) (679 ) Funded status and amount recognized at end of year $ (78,332 ) $ (59,999 ) $ (1,246 ) $ (1,412 ) $ (743 ) $ (679 ) Amounts recognized in the consolidated balance sheets Noncurrent asset $ — $ — $ — $ — $ — $ — Current liability — — (158 ) (159 ) (65 ) (54 ) Long-term liability (78,332 ) (59,999 ) (1,087 ) (1,253 ) (678 ) (625 ) Amounts recognized in accumulated other comprehensive income Net actuarial loss (gain) $ 47,101 $ 57,387 $ 415 $ 508 $ (4,313 ) $ (5,053 ) Prior service cost (credit) — — — — — — Accumulated other compensation income $ 47,101 $ 57,387 $ 415 $ 508 $ (4,313 ) $ (5,053 ) The projected benefit obligation and fair value of plan assets for pension plans with a projected benefit obligation in excess of plan assets at December 31, 2018 and 2017 were as follows (in thousands): Pension Benefits Pension Plan SERP 2018 2017 2018 2017 Projected benefit obligation in excess of plan assets Projected benefit obligation at end of year $ 381,483 $ 354,994 $ 1,246 $ 1,412 Fair value of plan assets at end of year 303,151 294,995 — — The projected benefit obligation, accumulated benefit obligation and fair value of plan assets for pension plans with an accumulated benefit obligation in excess of plan assets at December 31, 2018 and 2017 were as follows (in thousands): Pension Benefits Pension Plan SERP 2018 2017 2018 2017 Accumulated benefit obligation in excess of plan assets Projected benefit obligation at end of year $ 381,483 $ 354,994 $ 1,246 $ 1,412 Accumulated benefit obligation at end of year 356,797 324,904 1,246 1,412 Fair value of plan assets at end of year 303,151 294,995 — — The following tables presents the expected cash flows for the Company’s defined benefit plans and postretirement benefit plan at December 31, 2018 and 2017 (in thousands): Other Postretirement Benefits Pension Benefits Postretirement Welfare Plan Pension Plan SERP 2018 2017 2018 2017 2018 2017 Expected employer contributions First year $ 2,395 $ — $ 162 $ 162 $ 66 $ 48 Other Postretirement Benefits Pension Benefits Postretirement Welfare Plan Pension Plan SERP 2018 2017 2018 2017 2018 2017 Expected benefit payments (gross) Year one $ 12,209 $ 9,483 $ 162 $ 162 $ 66 $ 55 Year two 13,108 10,131 159 159 68 56 Year three 13,959 10,818 155 156 69 58 Year four 14,959 11,608 130 152 57 58 Year five 16,052 12,377 104 149 56 46 Next five years 96,547 75,717 447 462 261 214 Other Postretirement Benefits Pension Benefits Postretirement Welfare Plan Pension Plan SERP 2018 2017 2018 2017 2018 2017 Expected federal subsidy Year one $ — $ — $ — $ — $ — $ (7 ) Year two — — — — — (6 ) Year three — — — — — (6 ) Year four — — — — — (6 ) Year five — — — — — (7 ) Next five years — — — — — (30 ) The components of net periodic benefit cost and other changes in plan assets and benefit obligations recognized in other comprehensive income for the Company’s defined benefit plans for the years ended December 31, 2018, 2017 and 2016 were as follows (in thousands): Pension Benefits Pension Plan SERP 2018 2017 2016 2018 2017 2016 Components of net periodic benefit cost Service cost $ 7,622 $ 10,677 $ 13,402 $ — $ — $ — Interest cost 15,499 13,729 14,123 49 58 65 Expected return on plan assets (22,406 ) (18,195 ) (16,805 ) — — — Amortization: Actuarial loss 2,890 4,400 5,484 23 28 26 Prior service credit — — — — — — Net periodic benefit cost 3,605 10,611 16,204 72 86 91 Other changes in plan assets and benefit obligations recognized in other comprehensive income Current year actuarial loss (gain) (7,396 ) 7,562 15,203 (70 ) 42 12 Recognition of actuarial loss (2,890 ) (37,833 ) (5,484 ) (23 ) (28 ) (26 ) Recognition of prior service credit — — — — — — Total recognized in other comprehensive income (10,286 ) (30,271 ) 9,719 (93 ) 14 (14 ) Total recognized in net periodic benefit cost and other comprehensive income $ (6,681 ) $ (19,660 ) $ 25,923 $ (21 ) $ 100 $ 77 Weighted average assumptions used to determine net periodic benefit cost Discount rate (a) 3.7 % 4.2/4.0 % 4.5 % 3.7 % 4.2 % 4.5 % Expected long-term rate of return on plan assets 7.0 % 7.0 % 7.0 % — — — Rate of compensation increase Service- based table Service- based table Service- based table — — — (a) The 2018 discount rate for benefit cost for the Higman pension plan was changed from 4.13% as of February 14, 2018 and 4.02% as of March 31, 2018 to 4.40% as of December 31, 2018. In 2017, benefit cost for the pension plan was determined using a discount rate of 4.2% for the period beginning January 1, 2017 and ending April 11, 2017 and 4.0% for the period beginning April 12, 2017 and ending December 31, 2017. The estimated amounts that will be amortized from accumulated other comprehensive income into net periodic benefit cost in 2019 are as follows (in thousands): Pension Benefits Pension Plan SERP Actuarial loss $ 2,713 $ 28 Prior service credit — — $ 2,713 $ 28 The components of net periodic benefit cost and other changes in benefit obligations recognized in other comprehensive income for the Company’s postretirement benefit plan for the years ended December 31, 2018, 2017 and 2016 were as follows (in thousands): Other Postretirement Benefits Postretirement Welfare Plan 2018 2017 2016 Components of net periodic benefit cost Service cost $ — $ — $ — Interest cost 24 27 29 Amortization: Actuarial gain (596 ) (668 ) (747 ) Prior service cost — — — Net periodic benefit cost (572 ) (641 ) (718 ) Other changes in benefit obligations recognized in other comprehensive income Current year actuarial loss (gain) 144 52 (198 ) Recognition of actuarial gain 596 668 747 Recognition of prior service cost — — — Adjustment for actual Medicare Part D reimbursement — — (3 ) Total recognized in other comprehensive income 740 720 546 Total recognized in net periodic benefit cost and other comprehensive income $ 168 $ 79 $ (172 ) Weighted average assumptions used to determine net periodic benefit cost Discount rate 3.7 % 4.2 % 4.5 % Health care cost trend rate: Initial rate 7.0 % 7.0 % 6.5 % Ultimate rate 5.0 % 5.0 % 5.0 % Years to ultimate 2022 2021 2019 Effect of one-percentage-point change in assumed health care cost trend rate on aggregate service and interest cost Increase $ 3 $ 3 $ 4 Decrease (2 ) (3 ) (3 ) The estimated amounts that will be amortized from accumulated other comprehensive income into net periodic benefit cost in 2019 are as follows (in thousands): Other Postretirement Benefits Postretirement Welfare Plan Actuarial gain $ (540 ) Prior service cost — $ (540 ) The Company also contributes to a multiemployer pension plan pursuant to a collective bargaining agreement which covers certain vessel crew members of its coastal operations and expires on April 30, 2019. The Company began participation in the Seafarers Pension Trust (“SPT”) with the Penn Maritime, Inc. acquisition on December 14, 2012. Contributions to the SPT are made currently based on a per day worked basis and charged to expense as incurred and included in costs of sales and operating expenses in the consolidated statement of earnings. During 2018 and 2017, the Company made contributions of $671,000 and $896,000, respectively, to the SPT. The Company’s contributions to the SPT did not exceed 5% of total contributions to the SPT in 2017. Total contributions for 2018 are not yet available. The Company did not pay any material surcharges in 2017 or 2018. The federal identification number of the SPT is 13-6100329 and the Certified Zone Status is Green at December 31, 2017. The Company’s future minimum contribution requirements under the SPT are unavailable because actuarial reports for the 2018 plan year are not yet complete and such contributions are subject to negotiations between the employers and the unions. The SPT was not in endangered or critical status for the 2017 plan year, the latest period for which a report is available, as the funded status was in excess of 100%. Based on an actuarial valuation performed as of December 31, 2017, there would be no withdrawal liability if the Company chose to withdraw from the SPT although the Company currently has no intention of terminating its participation in the SPT. The Company also contributes to a multiemployer pension plan pursuant to a collective bargaining agreement which covers certain employees of its distribution and services segment in New Jersey and expires on October 8, 2023. The Company began participation in the Central Pension Fund of the International Union of Operating Engineers and Participating Employers (“CPF”) with the S&S acquisition on September 13, 2017. Contributions to the CPF are made currently based on a fixed hourly rate for each hour worked or paid basis (in some cases contributions are made as a percentage of gross pay) and charged to expense as incurred and included in costs of sales and operating expenses in the consolidated statement of earnings. During 2018 and 2017, the Company made contributions of $736,000 and $238,000, respectively, to the CPF. Total contributions for the 2018 plan year are not yet available. The Company did not pay any material surcharges in 2017 or 2018. The federal identification number of the CPF is 36-6052390 and the Certified Zone Status is Green at January 31, 2018. The Company’s future minimum contribution requirements under the CPF are unavailable because actuarial reports for the 2018 plan year, which ended January 31, 2019, are not yet complete and such contributions are subject to negotiations between the employers and the unions. The CPF was not in endangered or critical status for the 2017 plan year, the latest period for which a report is available, as the funded status was 94%. Based on an actuarial valuation performed as of January 31, 2017, there would be no withdrawal liability if the Company chose to withdraw from the CPF although the Company currently has no intention of terminating its participation in the CPF. In addition to the defined benefit plans, the Company sponsors various defined contribution plans for substantially all employees. The aggregate contributions to the plans were $22,392,000, $17,247,000 and $18,213,000 in 2018, 2017 and 2016, respectively.

Other Comprehensive Income

Other Comprehensive Income	12 Months Ended
	Dec. 31, 2018
Other Comprehensive Income [Abstract]
Other Comprehensive Income	(12) Other Comprehensive Income The Company’s changes in other comprehensive income for the years ended December 31, 2018, 2017 and 2016 were as follows (in thousands): 2018 2017 2016 Gross Amount Income Tax (Provision) Benefit Net Amount Gross Amount Income Tax (Provision) Benefit Net Amount Gross Amount Income Tax (Provision) Benefit Net Amount Pension and postretirement benefits (a): Amortization of net actuarial loss $ 2,317 $ (585 ) $ 1,732 $ 3,760 $ (1,417 ) $ 2,343 $ 4,763 $ (1,825 ) $ 2,938 Actuarial gains (losses) 7,322 (1,416 ) 5,906 25,776 (9,371 ) 16,405 (15,013 ) 5,754 (9,259 ) Adoption of ASU 2018-02 – reclassification to retained earnings — (7,925 ) (7,925 ) — — — — — — Foreign currency translation adjustments (819 ) — (819 ) (146 ) — (146 ) — — — Total $ 8,820 $ (9,926 ) $ (1,106 ) $ 29,390 $ (10,788 ) $ 18,602 $ (10,250 ) $ 3,929 $ (6,321 ) (a) Actuarial gains (losses) are amortized into other income (expense). (See Note 11 – Retirement Plans)

Earnings Per Share

Earnings Per Share	12 Months Ended
	Dec. 31, 2018
Earnings Per Share [Abstract]
Earnings Per Share	(13) Earnings Per Share The following table presents the components of basic and diluted earnings per share for the years ended December 31, 2018, 2017 and 2016 (in thousands, except per share amounts): 2018 2017 2016 Net earnings attributable to Kirby $ 78,452 $ 313,187 $ 141,406 Undistributed earnings allocated to restricted shares (324 ) (2,213 ) (999 ) Income available to Kirby common stockholders — basic 78,128 310,974 140,407 Undistributed earnings allocated to restricted shares 324 2,213 999 Undistributed earnings reallocated to restricted shares (323 ) (2,211 ) (997 ) Income available to Kirby common stockholders — diluted $ 78,129 $ 310,976 $ 140,409 Shares outstanding: Weighted average common stock issued and outstanding 59,804 55,702 53,834 Weighted average unvested restricted stock (247 ) (394 ) (380 ) Weighted average common stock outstanding — basic 59,557 55,308 53,454 Dilutive effect of stock options and restricted stock units 132 53 58 Weighted average common stock outstanding — diluted 59,689 55,361 53,512 Net earnings per share attributable to Kirby common stockholders: Basic $ 1.31 $ 5.62 $ 2.63 Diluted $ 1.31 $ 5.62 $ 2.62 Certain outstanding options to purchase approximately 384,000, 472,000 and 240,000 shares of common stock were excluded in the computation of diluted earnings per share as of December 31, 2018, 2017 and 2016, respectively, as such stock options would have been antidilutive.

Quarterly Results (Unaudited)

Quarterly Results (Unaudited)	12 Months Ended
	Dec. 31, 2018
Quarterly Results (Unaudited) [Abstract]
Quarterly Results (Unaudited)	(14) Quarterly Results (Unaudited) The unaudited quarterly results for the year ended December 31, 2018 were as follows (in thousands, except per share amounts): Three Months Ended March 31, 2018 June 30, 2018 September 30, 2018 December 31, 2018 Revenues $ 741,688 $ 802,671 $ 704,845 $ 721,493 Costs and expenses 692,866 747,260 636,906 740,344 Gain (loss) on disposition of assets 1,898 442 18 (390 ) Operating income (loss) 50,720 55,853 67,957 (19,241 ) Other income 1,591 1,541 1,454 1,140 Interest expense (9,780 ) (12,540 ) (12,345 ) (12,191 ) Earnings (loss) before taxes on income 42,531 44,854 57,066 (30,292 ) Benefit (provision) for taxes on income (9,865 ) (16,061 ) (15,116 ) 5,961 Net earnings (loss) 32,666 28,793 41,950 (24,331 ) Less: Net earnings attributable to noncontrolling interests (195 ) (191 ) (134 ) (106 ) Net earnings (loss) attributable to Kirby $ 32,471 $ 28,602 $ 41,816 $ (24,437 ) Net earnings (loss) per share attributable to Kirby common stockholders: Basic $ 0.54 $ 0.48 $ 0.70 $ (0.41 ) Diluted $ 0.54 $ 0.48 $ 0.70 $ (0.41 ) The unaudited quarterly results for the year ended December 31, 2017 were as follows (in thousands, except per share amounts): Three Months Ended March 31, 2017 June 30, 2017 September 30, 2017 December 31, 2017 Revenues $ 491,705 $ 473,328 $ 541,274 $ 708,111 Costs and expenses 445,760 425,937 488,186 756,423 Gain (loss) on disposition of assets 99 (139 ) (159 ) (4,288 ) Operating income (loss) 46,044 47,252 52,929 (52,600 ) Other income (expense) (589 ) 228 320 902 Interest expense (4,457 ) (4,465 ) (5,388 ) (7,162 ) Earnings (loss) before taxes on income 40,998 43,015 47,861 (58,860 ) Benefit (provision) for taxes on income (13,353 ) (17,043 ) (19,072 ) 290,357 Net earnings 27,645 25,972 28,789 231,497 Less: Net earnings attributable to noncontrolling interests (162 ) (194 ) (182 ) (178 ) Net earnings attributable to Kirby $ 27,483 $ 25,778 $ 28,607 $ 231,319 Net earnings per share attributable to Kirby common stockholders: Basic $ 0.51 $ 0.48 $ 0.52 $ 3.88 Diluted $ 0.51 $ 0.48 $ 0.52 $ 3.87 Quarterly basic and diluted earnings per share may not total to the full year per share amounts, as the weighted average number of shares outstanding for each quarter fluctuates as a result of the assumed exercise of stock options.

Contingencies and Commitments

Contingencies and Commitments	12 Months Ended
	Dec. 31, 2018
Contingencies and Commitments [Abstract]
Contingencies and Commitments	(15) Contingencies and Commitments In 2009, the Company was named a Potentially Responsible Party (“PRP”) in addition to a group of approximately 250 named PRPs under the Comprehensive Environmental Response, Compensation and Liability Act of 1981 (“CERCLA”) with respect to a Superfund site, the Portland Harbor Superfund site (“Portland Harbor”) in Portland, Oregon. The site was declared a Superfund site in December 2000 as a result of historical heavily industrialized use due to manufacturing, shipbuilding, petroleum storage and distribution, metals salvaging, and electrical power generation activities which led to contamination of Portland Harbor, an urban and industrial reach of the lower Willamette River located immediately downstream of downtown Portland. The Company’s involvement arises from four spills at the site after it was declared a Superfund site, as a result of predecessor entities’ actions in the area. To date, there is no information suggesting the extent of the costs or damages to be claimed from the 250 notified PRPs. Based on the nature of the involvement at the Portland Harbor site, the Company believes its potential contribution is de minimis; however, to date neither the Environmental Protection Agency (“EPA”) nor the named PRPs have performed an allocation of potential liability in connection with the site nor have they provided costs and expenses in connection with the site. In January 2015, the Company was named as a defendant in a Complaint filed in the U.S. District Court of the Southern District of Texas, USOR Site PRP Group vs. A&M Contractors, USES, Inc. et al. On October 13, 2016, the Company, as a successor to Hollywood Marine, Inc. (“Hollywood Marine”), was issued a General Notice under CERCLA in which it was named as a PRP for liabilities associated with the SBA Shipyard Site located near Jennings, Louisiana (“Site”). The Site was added to the EPA’s National Priorities List of sites under CERCLA in September 2016. SBA used the facility for construction, repair, retrofitting, sandblasting, and cleaning and painting of barges beginning in 1965. Three barge slips and a dry dock are located off the Mermentau River. The slips were used to dock barges during cleaning or repair. In 2001, a group of PRPs that had been former customers of the SBA Shipyard facility formed an organization called the SSIC Remediation, LLC (hereinafter, “the PRP Group Companies”) to address removal actions at the Site. In 2002, EPA approved an Interim Measures/Removal Action of Hazardous/Principal Threat Wastes at SBA Shipyards, Inc. (pursuant to RCRA Section 3008(h)) that was proposed by SBA Shipyard and the PRP Group Companies. Interim removal activities were conducted from March 2001 through January 2005 under an EPA 2002 Order and Agreement. In September 2012, the Louisiana Department of Environmental Quality requested EPA address the Site under CERCLA authority. The Company, as a successor to Hollywood Marine, joined the PRP Group Companies. The PRP Group Companies have submitted a draft Study work plan to EPA for their review and comment. Higman was named as a PRP in connection with its activities at the Site. Higman is not a participant in the PRP Group Companies. With respect to the above sites, the Company has recorded reserves, if applicable, for its estimated potential liability for its portion of the EPA’s past costs claim based on information developed to date including various factors such as the Company’s liability in proportion to other responsible parties and the extent to which such costs are recoverable from third parties. On October 13, 2016, the tug Nathan E. Stewart and barge DBL 55, an ATB, ran aground at the entrance to Seaforth Channel on Atholone Island, British Columbia. The grounding resulted in a breach of a portion of the Nathan E. Stewart’s fuel tanks causing a discharge of diesel fuel into the water. The USCG and the National Transportation Safety Board designated the Company as a party of interest in their investigation as to the cause of the incident. The Canadian authorities including Transport Canada and the Canadian Transportation Safety Board investigated the cause of the incident. On October 10, 2018, the Heiltsuk First Nation filed a civil action against a subsidiary of the Company, the master and pilot of the tug, the vessels and the Canadian government seeking unquantified damages as a result of the incident. On the same date, the Canadian government filed charges against the subsidiary and the vessels for violations of the Canadian Fisheries Act, the Migratory Birds Convention Act, the Pilotage Act and the Shipping Act of 2001. To date, there has been no activity in either pending case as deadlines to respond have been extended. The Company is unable to estimate the potential exposure in either proceeding. The Company has various insurance policies covering liabilities including pollution, property, marine and general liability and believes that it has satisfactory insurance coverage for the cost of cleanup and salvage operations as well as other potential liabilities arising from the incident. The Company believes it has accrued adequate reserves for the incident and does not expect the incident to have a material adverse effect on its business or financial condition. On March 22, 2014, two tank barges and a towboat (the M/V Miss Susan), owned by Kirby Inland Marine, LP, a wholly owned subsidiary of the Company, were involved in a collision with the M/S Summer Wind on the Houston Ship Channel near Texas City, Texas. The lead tank barge was damaged in the collision resulting in a discharge of intermediate fuel oil from one of its cargo tanks. The Company is participating in the natural resource damage assessment and restoration process with federal and state government natural resource trustees. The Company believes it has adequate insurance coverage for pollution, marine and other potential liabilities arising from the incident. The Company believes it has accrued adequate reserves for the incident and does not expect the incident to have a material adverse effect on its business or financial condition. In addition, the Company is involved in various legal and other proceedings which are incidental to the conduct of its business, none of which in the opinion of management will have a material effect on the Company’s financial condition, results of operations or cash flows. Management believes that it has recorded adequate reserves and believes that it has adequate insurance coverage or has meritorious defenses for these other claims and contingencies. Certain Significant Risks and Uncertainties. The customer base of the marine transportation segment includes major industrial petrochemical and chemical manufacturers, refining companies and agricultural chemical manufacturers operating in the United States. During 2018, approximately 65% of marine transportation’s inland revenues were from movements of such products under term contracts, typically ranging from one year to three years, some with renewal options. During 2018, approximately 80% of the marine transportation’s coastal revenues were under term contracts. While the manufacturing and refining companies have generally been customers of the Company for numerous years (some as long as 40 years) and management anticipates a continuing relationship, there is no assurance that any individual contract will be renewed. No single customer of the marine transportation segment accounted for 10% or more of the Company’s revenues in 2018, 2017 and 2016. Major customers of the distribution and services segment include oilfield service companies, oil and gas operators and producers, inland and offshore barge operators, offshore fishing companies, on-highway transportation companies, mining companies, construction companies, the United States government, and power generation, nuclear and industrial companies. The results of the distribution and services segment are largely tied to the industries it serves and, therefore, can be influenced by the cycles of such industries. No single customer of the distribution and services segment accounted for 10% of the Company’s revenues in 2018, 2017 and 2016. United has maintained continuous exclusive distribution rights for MTU and Allison Transmission products since 1946. United is one of MTU’s top five distributors of MTU off-highway engines in North America with exclusive distribution rights in Oklahoma, Arkansas, Louisiana and Mississippi. In addition, as a distributor of Allison Transmission products, United has distribution rights in Oklahoma, Arkansas and Louisiana. Finally, United is also the distributor for parts service and warranty on Daimler Truck North America (DTNA) engines and related equipment in Oklahoma, Arkansas and Louisiana. S&S is also one of MTU’s top five distributors for off-highway engines with exclusive distribution rights in multiple states. S&S also has authorized exclusive distribution rights for Allison Transmission, Detroit Diesel, Deutz, DTNA, EMD, Rolls Royce Power and Volvo Penta diesel engines in multiple key growth states, primarily through the Central, South and Eastern parts of the United States and strategically located near major oil and gas fields, marine waterways and on-highway transportation routes. In addition, S&S has long-term relationships with numerous smaller suppliers including Donaldson, Freightliner, Generac and John Deere. Kirby Engine Systems, through Marine Systems and Engine Systems, operates as an authorized EMD distributor throughout the United States. Engine Systems is also the authorized EMD distributor for nuclear power applications worldwide. The relationship with EMD has been maintained for 53 years. The segment also operates factory-authorized full service marine distributorship/dealerships for Cummins, Detroit Diesel and John Deere high-speed diesel engines and Falk, Lufkin and Twin Disc marine gears, as well as an authorized marine dealer for Caterpillar diesel engine in multiple states. Weather can be a major factor in the day-to-day operations of the marine transportation segment. Adverse weather conditions, such as high or low water, tropical storms, hurricanes, tsunamis, fog and ice, can impair the operating efficiencies of the marine fleet. Shipments of products can be delayed or postponed by weather conditions, which are totally beyond the control of the Company. Adverse water conditions are also factors which impair the efficiency of the fleet and can result in delays, diversions and limitations on night passages, and dictate horsepower requirements and size of tows. Additionally, much of the inland waterway system is controlled by a series of locks and dams designed to provide flood control, maintain pool levels of water in certain areas of the country and facilitate navigation on the inland river system. Maintenance and operation of the navigable inland waterway infrastructure is a government function handled by the Army Corps of Engineers with costs shared by industry. Significant changes in governmental policies or appropriations with respect to maintenance and operation of the infrastructure could adversely affect the Company. The Company’s marine transportation segment is subject to regulation by the USCG, federal laws, state laws and certain international conventions, as well as numerous environmental regulations. The Company believes that additional safety, environmental and occupational health regulations may be imposed on the marine industry. There can be no assurance that any such new regulations or requirements, or any discharge of pollutants by the Company, will not have an adverse effect on the Company. The Company’s marine transportation segment competes principally in markets subject to the Jones Act, a federal cabotage law that restricts domestic marine transportation in the United States to vessels built and registered in the United States, and manned and owned by United States citizens. The Jones Act cabotage provisions occasionally come under attack by interests seeking to facilitate foreign flag competition in trades reserved for domestic companies and vessels under the Jones Act. The Company believes that continued efforts will be made to modify or eliminate the cabotage provisions of the Jones Act. If such efforts are successful, certain elements could have an adverse effect on the Company. The Company has issued guaranties or obtained standby letters of credit and performance bonds supporting performance by the Company and its subsidiaries of contractual or contingent legal obligations of the Company and its subsidiaries incurred in the ordinary course of business. The aggregate notional value of these instruments is $20,133,000 at December 31, 2018, including $8,179,000 in letters of credit and $11,954,000 in performance bonds. All of these instruments have an expiration date within two years. The Company does not believe demand for payment under these instruments is likely and expects no material cash outlays to occur in connection with these instruments.

Segment Data

Segment Data	12 Months Ended
	Dec. 31, 2018
Segment Data [Abstract]
Segment Data	(16) Segment Data The Company’s operations are aggregated into two reportable business segments as follows: Marine Transportation Distribution and Services The Company’s two reportable business segments are managed separately based on fundamental differences in their operations. The Company’s accounting policies for the business segments are the same as those described in Note 1, Summary of Significant Accounting Policies. The Company evaluates the performance of its segments based on the contributions to operating income of the respective segments, and before income taxes, interest, gains or losses on disposition of assets, other nonoperating income, noncontrolling interests, accounting changes, and nonrecurring items. Intersegment revenues, based on market-based pricing, of the distribution and services segment from the marine transportation segment of $29,363,000, $20,717,000 and $24,672,000 in 2018, 2017 and 2016, respectively, as well as the related intersegment profit of $2,936,000, $2,072,000 and $2,467,000 in 2018, 2017 and 2016, respectively, have been eliminated from the tables below. The following table sets forth by reportable segment the revenues, profit or loss, total assets, depreciation and amortization, and capital expenditures attributable to the principal activities of the Company for the years ended December 31, 2018, 2017 and 2016 (in thousands): 2018 2017 2016 Revenues: Marine transportation $ 1,483,143 $ 1,324,106 $ 1,471,893 Distribution and services 1,487,554 890,312 298,780 $ 2,970,697 $ 2,214,418 $ 1,770,673 Segment profit (loss): Marine transportation $ 147,416 $ 135,547 $ 259,453 Distribution and services 129,305 86,479 3,068 Other (162,562 ) (149,012 ) (34,775 ) $ 114,159 $ 73,014 $ 227,746 Total assets: Marine transportation $ 4,145,294 $ 3,485,099 $ 3,613,951 Distribution and services 1,653,636 1,567,085 623,268 Other 72,664 75,243 52,676 $ 5,871,594 $ 5,127,427 $ 4,289,895 Depreciation and amortization: Marine transportation $ 182,307 $ 178,898 $ 184,291 Distribution and services 39,349 20,387 12,833 Other 3,316 3,596 3,793 $ 224,972 $ 202,881 $ 200,917 Capital expenditures: Marine transportation $ 284,953 $ 165,421 $ 217,423 Distribution and services 10,742 5,086 5,915 Other 6,166 6,715 7,728 $ 301,861 $ 177,222 $ 231,066 The following table presents the details of “Other” segment profit (loss) for the years ended December 31, 2018, 2017 and 2016 (in thousands): 2018 2017 2016 General corporate expenses $ (35,590 ) $ (18,202 ) $ (15,024 ) Interest expense (46,856 ) (21,472 ) (17,690 ) Impairment of long-lived assets (82,705 ) (105,712 ) — Impairment of goodwill (2,702 ) — — Lease cancellation costs (2,403 ) — — Gain (loss) on disposition of assets 1,968 (4,487 ) (127 ) Other income (expense) 5,726 861 (1,934 ) $ (162,562 ) $ (149,012 ) $ (34,775 ) The following table presents the details of “Other” total assets as of December 31, 2018, 2017 and 2016 (in thousands): 2018 2017 2016 General corporate assets $ 70,169 $ 73,353 $ 50,054 Investment in affiliates 2,495 1,890 2,622 $ 72,664 $ 75,243 $ 52,676

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2018
Related Party Transactions [Abstract]
Related Party Transactions	(17) Related Party Transactions The Company is a 50% owner of The Hollywood Camp, L.L.C. (“The Hollywood Camp”), a company that owns and operates a hunting and fishing facility used by the Company primarily for customer entertainment. The Hollywood Camp allocates lease and lodging expenses to its members based on their usage of the facilities. The Company paid The Hollywood Camp $4,523,000 in 2018, $3,634,000 in 2017 and $3,143,000 in 2016 for its share of facility expenses. The Company is a 50% owner of Bolivar Terminal Co., Inc. (“Bolivar”), a company that provides barge fleeting services (temporary barge storage facilities) in the Houston, Texas area. The Company paid Bolivar $461,000 in 2018, $581,000 in 2017 and $1,314,000 in 2016 for barge fleeting services. Such services were in the ordinary course of business of the Company. The husband of Amy D. Husted, Vice President and General Counsel of the Company, is a partner in the law firm of Clark Hill Strasburger. The Company paid the law firm $2,019,000 in 2018, $830,000 in 2017 and $779,000 in 2016 for legal services in connection with matters in the ordinary course of business of the Company.

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2018
SUBSEQUENT EVENTS [Abstract]
Subsequent Events	(18) Subsequent Event On January 29, 2019, the Company signed a definitive agreement to acquire the marine transportation fleet of Cenac Marine Services, LLC (“Cenac”) for approximately $244,000,000 in cash, subject to certain closing adjustments. The purchase will be financed through additional borrowings. Cenac’s fleet consists of 63 inland 30,000 barrel tank barges with approximately 1.9 million barrels of capacity, 34 inland towboats and two offshore tugboats. Cenac moves petrochemicals, refined products and black oil, including crude oil, residual fuels, feedstocks and lubricants on the lower Mississippi River, its tributaries, and the Gulf Intracoastal Waterway for major oil companies and refiners. On February 11, 2019, the Federal Trade Commission granted th Company early termination of the Hart-Scott-Rdino waiting period for the acquisition of Cenac. The closing of the acquisition is expected to occur in March 2019.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2018
Summary of Significant Accounting Policies [Abstract]
Principles of Consolidation	Principles of Consolidation.
Cash Equivalents	Cash Equivalents.
Accounts Receivable	Accounts Receivable. The Company’s marine transportation and distribution and services operations are subject to hazards associated with such businesses. The Company maintains insurance coverage against these hazards with insurance companies. Included in accounts receivable as of December 31, 2018 and 2017 were $69,624,000 and $66,588,000, respectively, of receivables from insurance companies to cover claims in excess of the Company’s deductible.
Concentrations of Credit Risk	Concentrations of Credit Risk.
Fair Value of Financial Instruments	Fair Value of Financial Instruments.
Property, Maintenance and Repairs	Property, Maintenance and Repairs.
Drydocking on Ocean-Going Vessels	Drydocking on Ocean-Going Vessels.
Environmental Liabilities	Environmental Liabilities.
Goodwill	Goodwill. During the 2018 fourth quarter, the Company took a $2,702,000 charge for the impairment of the remaining goodwill recorded for Osprey Line, L.L.C., a subsidiary that transports project cargoes and cargo containers by barge on the United States inland waterway system. The impairment reflected the reduced profitability outlook of the container-on-barge operations due to the current economic environment. The fair value was determined using a combination of a discounted cash flow methodology and a market based approach utilizing a net earnings before interest expense, taxes on income, depreciation and amortization (EBITDA) multiplier. Net goodwill for the marine transportation segment was $405,575,000 and $387,504,000 at December 31, 2018 and 2017, respectively. The increase in net goodwill for the marine transportation segment for 2018 was due to the acquisitions of Higman Marine, Inc. and its affiliated companies (“Higman”) and Targa Resources Corp.’s (“Targa”) inland tank barge business, more fully described in Note 3, Acquisitions. Net goodwill for the distribution and services segment was $548,251,000 and $547,631,000 at December 31, 2018 and 2017, respectively.
Other Intangibles	Other Intangibles. The costs of intangible assets and liabilities are amortized to expense in a systematic and rational manner over their estimated useful lives. For the years ended December 31, 2018, 2017 and 2016, the amortization expense for intangibles was $16,760,000, $11,296,000 and $8,467,000, respectively. Estimated amortization expense for amortizable intangible assets and liabilities for the next five years (2019 – 2023) is approximately $18,999,000, $20,854,000, $20,174,000, $19,824,000 and $19,782,000, respectively. As of December 31, 2018, the weighted average amortization period for intangible assets and liabilities was approximately 14 years.
Revenue Recognition	Revenue Recognition. Distribution products and services are generally sold based upon purchase orders or preferential service agreements with the customer that include fixed or determinable prices. Parts sales are recognized when control transfers to the customer, generally when title passes upon shipment to customers. Service revenue is recognized over time as the service is provided using measures of progress utilizing hours worked or costs incurred as a percentage of estimated hours or expected costs. Revenue from rental agreements is recognized on a straight-line basis over the rental period. The Company recognizes the revenues on contract manufacturing activities upon shipment and transfer of control to the customer. Prior to the adoption of Accounting Standards Update (“ASU”)
Stock-Based Compensation	Stock-Based Compensation.
Taxes on Income	Taxes on Income.
Accrued Insurance	Accrued Insurance.
Treasury Stock	Treasury Stock.
Impairment of Long-Lived Assets and for Long-Lived Assets to Be Disposed Of	Impairment of Long-lived Assets and for Long-lived Assets to Be Disposed Of. Recoverability on marine transportation assets is assessed based on vessel classes, not on individual assets, because identifiable cash flows for individual marine transportation assets are not available. Projecting customer contract volumes allows estimation of future cash flows by projecting pricing and utilization by vessel class but it is not practical to project which individual marine transportation asset will be utilized for any given contract. Because customers do not specify which particular vessel is used, prices are quoted based on vessel classes not individual assets. Nominations of vessels for specific jobs are determined on a day by day basis and are a function of the equipment class required and the geographic position of vessels within that class at that particular time as vessels within a class are interchangeable and provide the same service. The Company’s vessels are mobile assets and equipped to operate in geographic regions throughout the United States and the Company has in the past and expects to continue to move vessels from one region to another when it is necessary due to changing markets and it is economical to do so. Barge vessel classes are based on similar capacities, hull type, and type of product and towing vessels are based on similar hull type and horsepower. Recoverability of the vessel classes is measured by a comparison of the carrying amount of the assets to future net cash flows expected to be generated by the assets. If such assets are considered to be impaired, the impairment to be recognized is measured by the amount by which the carrying amount of the assets exceeds the fair value of the assets. Assets to be disposed of are reported at the lower of the carrying amount or fair value less costs to sell.
Accounting Standards	Accounting Standards In August 2018, the Financial Accounting Standards Board (“FASB”) issued ASU 2018-14, “Compensation – Retirement Benefits - Defined Benefit Plans – General (Subtopic 715-20): Disclosure Framework – Changes to the Disclosure Requirements for Defined Benefit Plans” which amends the annual disclosure requirements for employers that sponsor defined benefit pension or other postretirement plans by removing certain requirements, providing clarification on existing requirements and adding new requirements including adding an explanation of the reasons for significant gains and losses related to changes in the benefit obligation for the period. The guidance is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2020. Early adoption is permitted. The amendments in this update are required to be applied on a retrospective basis to all periods presented. The Company is currently evaluating this guidance to determine the impact on its disclosures. In February 2018, the FASB issued ASU 2018-02, “Income Statement – Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income” which allows a reclassification from accumulated other comprehensive income to retained earnings for stranded tax effects resulting from the recent federal tax reform legislation. ASU 2018-02 eliminates the stranded tax effects resulting from the recent federal tax reform legislation and will improve the usefulness of information reported to financial statement users. The amendments in ASU 2018-02 will be applied either in the period of adoption or retrospectively to each period (or periods) in which the effect of the change in the recent federal tax reform legislation is recognized. ASU 2018-02 is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2018. Early adoption is permitted, including adoption in any interim period, for which financial statements have not yet been made available for issuance. The Company elected to early adopt ASU 2018-02 in the 2018 first quarter, which resulted in the reclassification of $7,925,000 from accumulated other comprehensive income (loss) to retained earnings due to the change in the federal corporate tax rate. In March 2017, the FASB issued ASU 2017-07, “Compensation – Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost” (“ASU 2017-07”) which requires employers to include only the service cost component of net periodic pension cost and net periodic postretirement benefit cost in operating expenses. The other components of net benefit cost are required to be presented in the income statement separately from the service cost component and outside a subtotal of income from operations. The standard allows only the service cost component to be eligible for capitalization when applicable. ASU 2017-07 is effective for annual and interim periods beginning after December 15, 2017 with early adoption permitted. This standard shall be applied retrospectively for the presentation of the service cost component and the other components of net periodic pension cost and net periodic postretirement benefit cost in the income statement and prospectively for the capitalization of the service cost benefit in assets. The Company adopted ASU 2017-07 on January 1, 2018 and applied the standard retrospectively. The other components of net benefit cost are shown in Note 11, Retirement Plans. As a result of the adoption, the Company reclassified income of $621,000 for 2017 and expense of $2,175,000 for 2016 from operating expense into non-operating expense in the condensed statement of earnings. In January 2017, the FASB issued ASU 2017-04, “Intangibles – Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment” (“ASU 2017-04”) which simplifies the subsequent measurement of goodwill by eliminating Step 2 in the goodwill impairment test that required an entity to perform procedures to determine the fair value of its assets and liabilities at the testing date. An entity instead will perform its annual, or interim, goodwill impairment test by comparing the fair value of a reporting unit with its carrying value and record an impairment charge based on the excess of a reporting unit’s carrying amount over its fair value. An entity still has the option to perform the qualitative assessment for a reporting unit to determine if the quantitative impairment test is necessary. ASU 2017-04 will be applied prospectively and is effective for annual and interim goodwill impairment tests conducted in fiscal years beginning after December 15, 2019. Early adoption is permitted for interim or annual goodwill impairment testing dates after January 1, 2017. The Company is currently evaluating the impact, if any, that the adoption of this standard will have on its consolidated financial statements. In August 2016, the FASB issued ASU 2016-15, “Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments” (“ASU 2016-15”) to create consistency in practice in how certain cash receipts and cash payments are presented and classified in the statement of cash flows. ASU 2016-15 is effective for annual and interim periods beginning after December 15, 2017. Early adoption is permitted. The Company adopted ASU 2016-15 on January 1, 2018 and the adoption of the standard did not have a material impact on the consolidated financial statements. In February 2016, the FASB issued ASU No. 2016-02, “Leases (Topic 842)” (“ASU 2016-02”) to increase transparency and comparability among organizations by requiring recognition of lease assets and lease liabilities on the balance sheet and disclosure of key information about leasing arrangements. The Company will adopt ASU 2016-02 on January 1, 2019 under the optional transition method that allows for a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption and will not restate prior periods. The Company will also elect certain practical expedients permitted under the transition guidance. While the Company is continuing to assess the potential impacts of ASU 2016-02, the Company estimates that the adoption of ASU 2016-02 will result in the recognition of right-of-use assets for operating leases of approximately $185,000,000 and lease liabilities for operating leases of approximately $180,000,000 on its Consolidated Balance Sheets, with no material impact to its Consolidated Statements of Earnings or Cash Flows. The Company does not have any financing leases as of January 1, 2019. In May 2014, the FASB issued ASU 2014-09, “Revenue from Contracts with Customers (ASC Topic 606)” (“ASU 2014-09” or “ASC 606”). ASU 2014-09 requires an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers. ASU 2014-09 replaces most existing revenue recognition guidance in United States Generally Accepted Accounting Principles and is effective for fiscal years, and interim periods within those years, beginning after December 15, 2017. ASU 2014-09 permits the use of either the retrospective, modified retrospective or prospective with a cumulative catch-up approach. The Company adopted ASU 2014-09 on January 1, 2018 under the modified retrospective approach with a cumulative adjustment that decreased the opening balance of retained earnings by $9,722,000. Prior period amounts were not adjusted and the prior period amounts continue to be reported under the accounting standards in effect for those periods. The cumulative adjustment primarily relates to recognition of revenue on certain contract manufacturing activities, primarily construction of new pressure pumping units in the Company’s distribution and services segment. The Company previously recognized revenue on manufacturing and assembly projects on a percentage of completion method using measurements of progress towards completion appropriate for the work performed. Upon the adoption of ASU 2014-09, the Company recognizes the revenues on contract manufacturing activities upon shipment and transfer of control versus the percentage of completion method. The following tables summarize the financial statement line items within the Company’s condensed consolidated financial statements impacted by ASU 2014-09 for the year ended December 31, 2018 (in thousands): 2018 As Reported Balances without Adoption of ASC 606 Effect of Change Statements of earnings: Distribution and services revenues $ 1,487,554 $ 1,515,554 $ (28,000 ) Costs of sales and operating expenses $ 2,160,946 $ 2,181,046 $ (20,100 ) Operating income $ 155,289 $ 163,189 $ (7,900 ) Earnings before taxes on income $ 114,159 $ 122,059 $ (7,900 ) Provision for taxes on income $ (35,081 ) $ (37,187 ) $ 2,106 Net earnings attributable to Kirby $ 78,452 $ 84,246 $ (5,794 ) Statements of comprehensive income: Net earnings $ 79,078 $ 84,872 $ (5,794 ) Comprehensive income attributable to Kirby $ 77,346 $ 83,140 $ (5,794 ) Statements of cash flows: Net earnings $ 79,078 $ 84,872 $ (5,794 ) Provision for deferred income taxes $ 34,881 $ 32,775 $ 2,106 Decrease in cash flows resulting from changes in: Accounts receivable $ 12,511 $ (71,624 ) $ 84,135 Inventory $ (144,685 ) $ (71,985 ) $ (72,700 ) Accrued and other liabilities $ 30,712 $ 38,459 $ (7,747 ) The following table summarizes the balance sheet line items within the Company’s condensed consolidated financial statements as of December 31, 2018 impacted by ASU 2014-09 (in thousands): December 31, 2018 As Reported Balances without Adoption of ASC 606 Effect of Change Balance sheets: Trade receivables $ 417,644 $ 501,779 $ (84,135 ) Inventories – net $ 507,441 $ 434,741 $ 72,700 Total assets $ 5,871,594 $ 5,883,029 $ (11,435 ) Deferred revenues $ 80,123 $ 70,858 $ 9,265 Deferred income taxes $ 542,785 $ 547,991 $ (5,206 ) Retained earnings $ 2,723,592 $ 2,739,086 $ (15,494 ) Total liabilities and equity $ 5,871,594 $ 5,883,029 $ (11,435 )

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2018
Summary of Significant Accounting Policies [Abstract]
Condensed Consolidated Financial Statements Impacted by ASU 2014-09	The following tables summarize the financial statement line items within the Company’s condensed consolidated financial statements impacted by ASU 2014-09 for the year ended December 31, 2018 (in thousands): 2018 As Reported Balances without Adoption of ASC 606 Effect of Change Statements of earnings: Distribution and services revenues $ 1,487,554 $ 1,515,554 $ (28,000 ) Costs of sales and operating expenses $ 2,160,946 $ 2,181,046 $ (20,100 ) Operating income $ 155,289 $ 163,189 $ (7,900 ) Earnings before taxes on income $ 114,159 $ 122,059 $ (7,900 ) Provision for taxes on income $ (35,081 ) $ (37,187 ) $ 2,106 Net earnings attributable to Kirby $ 78,452 $ 84,246 $ (5,794 ) Statements of comprehensive income: Net earnings $ 79,078 $ 84,872 $ (5,794 ) Comprehensive income attributable to Kirby $ 77,346 $ 83,140 $ (5,794 ) Statements of cash flows: Net earnings $ 79,078 $ 84,872 $ (5,794 ) Provision for deferred income taxes $ 34,881 $ 32,775 $ 2,106 Decrease in cash flows resulting from changes in: Accounts receivable $ 12,511 $ (71,624 ) $ 84,135 Inventory $ (144,685 ) $ (71,985 ) $ (72,700 ) Accrued and other liabilities $ 30,712 $ 38,459 $ (7,747 ) The following table summarizes the balance sheet line items within the Company’s condensed consolidated financial statements as of December 31, 2018 impacted by ASU 2014-09 (in thousands): December 31, 2018 As Reported Balances without Adoption of ASC 606 Effect of Change Balance sheets: Trade receivables $ 417,644 $ 501,779 $ (84,135 ) Inventories – net $ 507,441 $ 434,741 $ 72,700 Total assets $ 5,871,594 $ 5,883,029 $ (11,435 ) Deferred revenues $ 80,123 $ 70,858 $ 9,265 Deferred income taxes $ 542,785 $ 547,991 $ (5,206 ) Retained earnings $ 2,723,592 $ 2,739,086 $ (15,494 ) Total liabilities and equity $ 5,871,594 $ 5,883,029 $ (11,435 )

Revenues (Tables)

Revenues (Tables)	12 Months Ended
	Dec. 31, 2018
Revenues [Abstract]
Revenues by Major Source	The following table sets forth the Company’s revenues by major source for the years ended December 31, 2018, 2017 and 2016 (in thousands): 2018 2017 2016 Marine transportation segment: Inland transportation $ 1,119,820 $ 923,916 $ 951,097 Coastal transportation 363,323 400,190 520,796 $ 1,483,143 $ 1,324,106 $ 1,471,893 Distribution and services segment: Oil and gas $ 1,010,410 $ 614,128 $ 115,012 Commercial and industrial 477,144 276,184 183,768 $ 1,487,554 $ 890,312 $ 298,780

Acquisitions (Tables)

Acquisitions (Tables)	12 Months Ended
	Dec. 31, 2018
Acquisitions [Abstract]
Fair Values of Assets Acquired and Liabilities Assumed	The fair values of the assets acquired and liabilities assumed recorded at the acquisition date were as follows (in thousands): Assets: Cash $ 2,313 Accounts receivable 27,527 Prepaid expenses 5,323 Property and equipment 497,951 Goodwill 4,657 Other assets 30 Total assets $ 537,801 Liabilities: Accounts payable 17,012 Accrued liabilities 14,127 Deferred income taxes 40,524 Other long-term liabilities 44,216 Total liabilities $ 115,879 Net assets acquired $ 421,922
Pro Forma Revenues and Net Earnings	The following table sets forth the Company’s pro forma revenues and net earnings attributable to Kirby for the years ended December 31, 2016 and 2017 (unaudited and in thousands): 2016 Pro forma 2017 Pro forma Revenues $ 2,299,800 $ 2,556,131 Net earnings attributable to Kirby $ 125,197 $ 303,097

Inventories (Tables)

Inventories (Tables)	12 Months Ended
	Dec. 31, 2018
Inventories [Abstract]
Details of Inventories	The following table presents the details of inventories as of December 31, 2018 and 2017 (in thousands): December 31, 2018 December 31, 2017 Finished goods $ 406,364 $ 242,333 Work in process 101,077 73,396 $ 507,441 $ 315,729

Long-Term Debt (Tables)

Long-Term Debt (Tables)	12 Months Ended
	Dec. 31, 2018
Long-Term Debt [Abstract]
Long-Term Debt	Long-term debt at December 31, 2018 and 2017 consisted of the following (in thousands): 2018 2017 Long-term debt, including current portion: $850,000,000 revolving credit facility due June 26, 2022 $ 417,373 $ 495,845 $150,000,000 senior notes Series A due February 27, 2020 150,000 150,000 $350,000,000 senior notes Series B due February 27, 2023 350,000 350,000 $500,000,000 senior notes due March 1, 2028 500,000 — $10,000,000 credit line due June 30, 2019 — — Bank notes payable 19 3 1,417,392 995,848 Unamortized debt issuance costs (6,550 ) (3,442 ) Unamortized debt discount (654 ) — $ 1,410,188 $ 992,406
Aggregate Payments due on the Long-Term Debt	The aggregate payments due on the long-term debt in each of the next five years were as follows (in thousands): 2019 $ 19 2020 150,000 2021 — 2022 417,373 2023 350,000 Thereafter 500,000 $ 1,417,392

Taxes on Income (Tables)

Taxes on Income (Tables)	12 Months Ended
	Dec. 31, 2018
Taxes on Income [Abstract]
Earnings Before Taxes	Earnings before taxes on income and details of the provision for taxes on income for the years ended December 31, 2018, 2017 and 2016 were as follows (in thousands): 2018 2017 2016 Earnings (loss) before taxes on income: United States $ 117,800 $ 74,267 $ 227,746 Foreign (3,641 ) (1,253 ) — $ 114,159 $ 73,014 $ 227,746 Provision (benefit) for taxes on income: U.S. Federal: Current $ — $ 11,143 $ 28,919 Deferred 27,102 (258,703 ) 49,685 $ 27,102 $ (247,560 ) $ 78,604 U.S. State: Current $ (243 ) $ 3,861 $ 4,727 Deferred 7,619 2,280 1,611 $ 7,376 $ 6,141 $ 6,338 Foreign: Current $ 443 $ 370 $ — Deferred 160 160 — $ 603 $ 530 $ — Consolidated: Current $ 200 $ 15,374 $ 33,646 Deferred 34,881 (256,263 ) 51,296 $ 35,081 $ (240,889 ) $ 84,942
Effective Income Tax Rate Reconciliation	The Company’s provision for taxes on income varied from the statutory federal income tax rate for the years ended December 31, 2018, 2017 and 2016 due to the following: 2018 2017 2016 United States income tax statutory rate 21.0 % 35.0 % 35.0 % State and local taxes, net of federal benefit 6.5 0.9 1.8 Change due to U.S. tax reform — (369.0 ) — Other – net 3.2 3.2 0.5 30.7 % (329.9 )% 37.3 %
Deferred Tax Assets and Liabilities	The tax effects of temporary differences that give rise to significant portions of the non-current deferred tax assets and liabilities at December 31, 2018 and 2017 were as follows (in thousands): 2018 2017 Non-current deferred tax assets and liabilities: Deferred tax assets: Allowance for doubtful accounts $ 2,105 $ 1,875 Inventory 5,017 3,795 Insurance accruals 4,119 4,599 Deferred compensation 1,291 1,849 Unrealized loss on defined benefit plans 9,891 11,097 Operating loss carryforwards 81,867 15,540 Pension benefits 6,559 549 Other 22,421 16,301 133,270 55,605 Valuation allowances (25,568 ) (15,308 ) 107,702 40,297 Deferred tax liabilities: Property (526,873 ) (428,947 ) Deferred state taxes (74,638 ) (58,366 ) Goodwill and other intangibles (34,235 ) (9,015 ) Other (14,741 ) (12,420 ) (650,487 ) (508,748 ) $ (542,785 ) $ (468,451 )
Reconciliation of Liability for Unrecognized Tax Benefits	A reconciliation of the beginning and ending amount of the liability for unrecognized tax benefits for the years ended December 31, 2018, 2017 and 2016, is as follows (in thousands): 2018 2017 2016 Balance at beginning of year $ 1,787 $ 2,019 $ 1,958 Additions based on tax positions related to the current year 254 403 187 Additions for tax positions of prior years 70 273 867 Reductions for tax positions of prior years (668 ) (908 ) (441 ) Settlements — — (552 ) Balance at end of year $ 1,443 $ 1,787 $ 2,019

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2018
Leases [Abstract]
Rent Expense	Total rental expense for the years ended December 31, 2018, 2017 and 2016 was as follows (in thousands): 2018 2017 2016 Rental expense: Marine equipment — barges $ 10,234 $ 11,550 $ 13,791 Marine equipment — towing vessels 140,389 116,690 137,609 Other buildings and equipment 23,365 15,915 11,182 Rental expense $ 173,988 $ 144,155 $ 162,582
Future Minimum Lease Payments under Operating Leases	Future minimum lease payments under operating leases that have initial or remaining noncancelable lease terms in excess of one year at December 31, 2018 were as follows (in thousands): Land, Buildings Marine Equipment And Equipment Barges Towing Vessels Total 2019 $ 19,524 $ 6,808 $ 70,759 $ 97,091 2020 16,916 5,400 7,746 30,062 2021 15,112 4,128 2,578 21,818 2022 13,547 4,138 2,578 20,263 2023 11,821 3,030 2,578 17,429 Thereafter 75,818 7,098 9,023 91,939 $ 152,738 $ 30,602 $ 95,262 $ 278,602

Stock Award Plans (Tables)

Stock Award Plans (Tables)	12 Months Ended
	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation Cost Breakdown in Statement of Earnings	The Company has share-based compensation plans which are described below. The compensation cost that has been charged against earnings for the Company’s stock award plans and the income tax benefit recognized in the statement of earnings for stock awards for the years ended December 31, 2018, 2017 and 2016 were as follows (in thousands): 2018 2017 2016 Compensation cost $ 19,104 $ 11,460 $ 11,675 Income tax benefit $ 5,903 $ 4,333 $ 4,378
Stock Option Valuation Assumptions	The key input variables used in valuing the stock options during the years ended December 31, 2018, 2017 and 2016 were as follows: 2018 2017 2016 Dividend yield None None None Average risk-free interest rate 2.7 % 2.0 % 1.5 % Stock price volatility 27 % 27 % 30 % Estimated option term Six years Six years Six years
Employee Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Option Activity	The following is a summary of the stock option activity under the employee plan described above for the years ended December 31, 2018, 2017 and 2016: Outstanding Non- Qualified or Nonincentive Stock Awards Weighted Average Exercise Price Outstanding at December 31, 2015 430,432 $ 71.01 Granted 186,706 $ 53.50 Canceled or expired (16,017 ) $ 80.17 Outstanding at December 31, 2016 601,121 $ 65.33 Granted 123,141 $ 68.46 Exercised (36,616 ) $ 47.95 Canceled or expired (32,991 ) $ 74.07 Outstanding at December 31, 2017 654,655 $ 66.45 Granted 115,797 $ 75.50 Exercised (283,886 ) $ 61.81 Canceled or expired (21,864 ) $ 102.42 Outstanding at December 31, 2018 464,702 $ 69.85
Outstanding and Exercisable Stock Options	The following table summarizes information about the Company’s outstanding and exercisable stock options under the employee plan at December 31, 2018: Options Outstanding Options Exercisable Range of Exercise Prices Number Outstanding Weighted Average Remaining Contractual Life in Years Weighted Average Exercise Price Aggregated Intrinsic Value Number Exercisable Weighted Average Exercise Price Aggregated Intrinsic Value $51.23 90,975 4.1 $ 51.23 57,438 $ 51.23 $64.65 – $68.50 126,260 4.7 $ 67.23 41,146 $ 67.40 $70.65 – $75.50 207,156 4.5 $ 74.56 91,359 $ 73.36 $93.64 – $101.46 40,311 2.1 $ 95.90 40,311 $ 95.90 $51.23 – $101.46 464,702 4.3 $ 69.85 $1,570,000 230,254 $ 70.72 $951,000
Restricted Stock Award Activity	The following is a summary of the restricted stock award activity under the employee plan described above for the years ended December 31, 2018, 2017 and 2016: Unvested Restricted Stock Award Shares Weighted Average Grant Date Fair Value Per Share Nonvested balance at December 31, 2015 311,727 $ 75.73 Granted 190,610 $ 53.56 Vested (105,109 ) $ 69.93 Forfeited (19,573 ) $ 76.06 Nonvested balance at December 31, 2016 377,655 $ 66.14 Granted 127,255 $ 68.50 Vested (105,600 ) $ 68.91 Forfeited (35,189 ) $ 69.45 Nonvested balance at December 31, 2017 364,121 $ 65.84 Vested (144,265 ) $ 72.66 Forfeited (5,640 ) $ 64.60 Nonvested balance at December 31, 2018 214,216 $ 64.73
RSU Activity	The following is a summary of RSU activity under the employee plan described above for the year ended December 31, 2018: Unvested RSUs Weighted Average Grant Date Fair Value Per Unit Nonvested balance at December 31, 2017 — $ — Granted 143,890 $ 75.59 Forfeited (2,835 ) $ 75.50 Nonvested balance at December 31, 2018 141,055 $ 75.59
Director Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Option Activity	The following is a summary of the stock option activity under the director plan described above for the years ended December 31, 2018, 2017, and 2016: Outstanding Non- Qualified or Nonincentive Stock Awards Weighted Average Exercise Price Outstanding at December 31, 2015 220,429 $ 64.37 Exercised (9,000 ) $ 35.72 Canceled or expired (6,000 ) $ 99.52 Outstanding at December 31, 2016 205,429 $ 64.60 Granted 3,188 $ 70.65 Exercised (39,000 ) $ 46.23 Canceled or expired (12,000 ) $ 87.35 Outstanding at December 31, 2017 157,617 $ 67.54 Granted 2,640 $ 85.30 Exercised (29,153 ) $ 57.47 Outstanding at December 31, 2018 131,104 $ 70.14
Outstanding and Exercisable Stock Options	The following table summarizes information about the Company’s outstanding and exercisable stock options under the director plan at December 31, 2018: Options Outstanding Options Exercisable Range of Exercise Prices Number Outstanding Weighted Average Remaining Contractual Life in Years Weighted Average Exercise Price Aggregate Intrinsic Value Number Exercisable Weighted Average Exercise Price Aggregate Intrinsic Value $29.60 6,000 0.3 $ 29.60 6,000 $ 29.60 $41.24 – $56.45 31,276 1.9 $ 50.61 31,276 $ 50.61 $61.89 – $62.48 28,000 3.6 $ 62.27 28,000 $ 62.27 $70.65 – $99.52 65,828 5.2 $ 86.45 65,168 $ 86.47 $29.60 – $99.52 131,104 3.8 $ 70.14 $893,000 130,444 $ 70.06 $893,000
Restricted Stock Award Activity	The following is a summary of the restricted stock award activity under the director plan described above for the years ended December 31, 2018, 2017 and 2016: Unvested Restricted Stock Award Shares Weighted Average Grant Date Fair Value Per Share Nonvested balance at December 31, 2015 1,791 $ 68.73 Granted 23,074 $ 64.89 Vested (24,518 ) $ 65.17 Nonvested balance at December 31, 2016 347 $ 64.89 Granted 21,198 $ 70.65 Vested (21,226 ) $ 70.56 Nonvested balance at December 31, 2017 319 $ 70.65 Granted 21,373 $ 85.70 Vested (21,428 ) $ 85.48 Nonvested balance at December 31, 2018 264 $ 85.30

Retirement Plans (Tables)

Retirement Plans (Tables)	12 Months Ended
	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Asset Allocation	As of December 31, 2018 and 2017, these assets were allocated among asset categories as follows: Asset Category 2018 2017 Current Minimum, Target and Maximum Allocation Policy U.S. equity securities 52 % 51 % 30% — 50%— 70 % International equity securities 17 % 21 % 0% — 20%— 30 % Debt securities 28 % 28 % 15% — 30%— 55 % Cash and cash equivalents 3 % — % 0% — 0%— 5 % 100 % 100 %
Change in Benefit Obligation	The following table presents the change in benefit obligation and plan assets for the Company’s defined benefit plans and postretirement benefit plan (in thousands): Other Postretirement Benefits Pension Benefits Postretirement Welfare Plan Pension Plan SERP 2018 2017 2018 2017 2018 2017 Change in benefit obligation Benefit obligation at beginning of year $ 354,994 $ 337,176 $ 1,412 $ 1,457 $ 679 $ 675 Service cost 7,622 10,677 — — — — Interest cost 15,499 13,729 49 58 24 27 Actuarial loss (gain) (44,935 ) 34,563 (70 ) 42 143 52 Gross benefits paid (11,749 ) (7,718 ) (145 ) (145 ) (103 ) (75 ) Curtailments (3,081 ) (33,433 ) — — — — Acquisition 63,133 — — — — — Benefit obligation at end of year $ 381,483 $ 354,994 $ 1,246 $ 1,412 $ 743 $ 679 Accumulated benefit obligation at end of year $ 356,797 $ 324,904 $ 1,246 $ 1,412 $ 743 $ 679
Weighted-Average Assumption Used to Determine Benefit Obligation and Net Periodic Benefit Cost	Weighted-average assumption used to determine benefit obligation at end of year Discount rate (a) 4.4 % 3.7 % 4.4 % 3.7 % 4.4 % 3.7 % Rate of compensation increase Service-based table Service-based table — — — — Health care cost trend rate Initial rate — — — — 7.0 % 7.0 % Ultimate rate — — — — 5.0 % 5.0 % Years to ultimate — — — — 2025 2022 (a) The discount rate for the Higman pension plan in 2018 was changed from 4.13% as of February 14, 2018 and 4.02% as of March 31, 2018 to 4.40% as of December 31, 2018.
Effect of One-Percentage-Point Change in Assumed Health Care Cost Trend Rate	Effect of one-percentage-point change in assumed health care cost trend rate on postretirement obligation Increase $ — $ — $ — $ — $ 75 $ 75 Decrease — — — — (65 ) (65 )
Change in Plan Assets	Change in plan assets Fair value of plan assets at beginning of year $ 294,995 $ 257,517 $ — $ — $ — $ — Actual return on plan assets (18,214 ) 45,196 — — — — Employer contribution 8,102 — 145 145 103 75 Gross benefits paid (11,749 ) (7,718 ) (145 ) (145 ) (103 ) (75 ) Acquisition 30,017 — — — — — Fair value of plan assets at end of year $ 303,151 $ 294,995 $ — $ — $ — $ —
Funded Status at End of Year	The following table presents the funded status and amounts recognized in the Company’s consolidated balance sheet for the Company’s defined benefit plans and postretirement benefit plan at December 31, 2018 and 2017 (in thousands): Other Postretirement Benefits Pension Benefits Postretirement Welfare Plan Pension Plan SERP 2018 2017 2018 2017 2018 2017 Funded status at end of year Fair value of plan assets $ 303,151 $ 294,995 $ — $ — $ — $ — Benefit obligations (381,483 ) (354,994 ) (1,246 ) (1,412 ) (743 ) (679 ) Funded status and amount recognized at end of year $ (78,332 ) $ (59,999 ) $ (1,246 ) $ (1,412 ) $ (743 ) $ (679 )
Amounts Recognized in the Consolidated Balance Sheets	Amounts recognized in the consolidated balance sheets Noncurrent asset $ — $ — $ — $ — $ — $ — Current liability — — (158 ) (159 ) (65 ) (54 ) Long-term liability (78,332 ) (59,999 ) (1,087 ) (1,253 ) (678 ) (625 )
Amounts Recognized in Accumulated Other Comprehensive Income	Amounts recognized in accumulated other comprehensive income Net actuarial loss (gain) $ 47,101 $ 57,387 $ 415 $ 508 $ (4,313 ) $ (5,053 ) Prior service cost (credit) — — — — — — Accumulated other compensation income $ 47,101 $ 57,387 $ 415 $ 508 $ (4,313 ) $ (5,053 )
Projected Benefit Obligation in Excess of Plan Assets	The projected benefit obligation and fair value of plan assets for pension plans with a projected benefit obligation in excess of plan assets at December 31, 2018 and 2017 were as follows (in thousands): Pension Benefits Pension Plan SERP 2018 2017 2018 2017 Projected benefit obligation in excess of plan assets Projected benefit obligation at end of year $ 381,483 $ 354,994 $ 1,246 $ 1,412 Fair value of plan assets at end of year 303,151 294,995 — —
Accumulated Benefit Obligation in Excess of Plan Assets	The projected benefit obligation, accumulated benefit obligation and fair value of plan assets for pension plans with an accumulated benefit obligation in excess of plan assets at December 31, 2018 and 2017 were as follows (in thousands): Pension Benefits Pension Plan SERP 2018 2017 2018 2017 Accumulated benefit obligation in excess of plan assets Projected benefit obligation at end of year $ 381,483 $ 354,994 $ 1,246 $ 1,412 Accumulated benefit obligation at end of year 356,797 324,904 1,246 1,412 Fair value of plan assets at end of year 303,151 294,995 — —
Employer Contribution	The following tables presents the expected cash flows for the Company’s defined benefit plans and postretirement benefit plan at December 31, 2018 and 2017 (in thousands): Other Postretirement Benefits Pension Benefits Postretirement Welfare Plan Pension Plan SERP 2018 2017 2018 2017 2018 2017 Expected employer contributions First year $ 2,395 $ — $ 162 $ 162 $ 66 $ 48
Expected Benefit Payments	Other Postretirement Benefits Pension Benefits Postretirement Welfare Plan Pension Plan SERP 2018 2017 2018 2017 2018 2017 Expected benefit payments (gross) Year one $ 12,209 $ 9,483 $ 162 $ 162 $ 66 $ 55 Year two 13,108 10,131 159 159 68 56 Year three 13,959 10,818 155 156 69 58 Year four 14,959 11,608 130 152 57 58 Year five 16,052 12,377 104 149 56 46 Next five years 96,547 75,717 447 462 261 214
Expected Federal Subsidy	Other Postretirement Benefits Pension Benefits Postretirement Welfare Plan Pension Plan SERP 2018 2017 2018 2017 2018 2017 Expected federal subsidy Year one $ — $ — $ — $ — $ — $ (7 ) Year two — — — — — (6 ) Year three — — — — — (6 ) Year four — — — — — (6 ) Year five — — — — — (7 ) Next five years — — — — — (30 )
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Net Periodic Benefit Cost	The components of net periodic benefit cost and other changes in plan assets and benefit obligations recognized in other comprehensive income for the Company’s defined benefit plans for the years ended December 31, 2018, 2017 and 2016 were as follows (in thousands): Pension Benefits Pension Plan SERP 2018 2017 2016 2018 2017 2016 Components of net periodic benefit cost Service cost $ 7,622 $ 10,677 $ 13,402 $ — $ — $ — Interest cost 15,499 13,729 14,123 49 58 65 Expected return on plan assets (22,406 ) (18,195 ) (16,805 ) — — — Amortization: Actuarial loss 2,890 4,400 5,484 23 28 26 Prior service credit — — — — — — Net periodic benefit cost 3,605 10,611 16,204 72 86 91 Other changes in plan assets and benefit obligations recognized in other comprehensive income Current year actuarial loss (gain) (7,396 ) 7,562 15,203 (70 ) 42 12 Recognition of actuarial loss (2,890 ) (37,833 ) (5,484 ) (23 ) (28 ) (26 ) Recognition of prior service credit — — — — — — Total recognized in other comprehensive income (10,286 ) (30,271 ) 9,719 (93 ) 14 (14 ) Total recognized in net periodic benefit cost and other comprehensive income $ (6,681 ) $ (19,660 ) $ 25,923 $ (21 ) $ 100 $ 77 Weighted average assumptions used to determine net periodic benefit cost Discount rate (a) 3.7 % 4.2/4.0 % 4.5 % 3.7 % 4.2 % 4.5 % Expected long-term rate of return on plan assets 7.0 % 7.0 % 7.0 % — — — Rate of compensation increase Service- based table Service- based table Service- based table — — — (a) The 2018 discount rate for benefit cost for the Higman pension plan was changed from 4.13% as of February 14, 2018 and 4.02% as of March 31, 2018 to 4.40% as of December 31, 2018. In 2017, benefit cost for the pension plan was determined using a discount rate of 4.2% for the period beginning January 1, 2017 and ending April 11, 2017 and 4.0% for the period beginning April 12, 2017 and ending December 31, 2017.
Estimated Amounts that will be Amortized from Accumulated Other Comprehensive Income into Net Periodic Benefit Cost	The estimated amounts that will be amortized from accumulated other comprehensive income into net periodic benefit cost in 2019 are as follows (in thousands): Pension Benefits Pension Plan SERP Actuarial loss $ 2,713 $ 28 Prior service credit — — $ 2,713 $ 28
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Net Periodic Benefit Cost	The components of net periodic benefit cost and other changes in benefit obligations recognized in other comprehensive income for the Company’s postretirement benefit plan for the years ended December 31, 2018, 2017 and 2016 were as follows (in thousands): Other Postretirement Benefits Postretirement Welfare Plan 2018 2017 2016 Components of net periodic benefit cost Service cost $ — $ — $ — Interest cost 24 27 29 Amortization: Actuarial gain (596 ) (668 ) (747 ) Prior service cost — — — Net periodic benefit cost (572 ) (641 ) (718 ) Other changes in benefit obligations recognized in other comprehensive income Current year actuarial loss (gain) 144 52 (198 ) Recognition of actuarial gain 596 668 747 Recognition of prior service cost — — — Adjustment for actual Medicare Part D reimbursement — — (3 ) Total recognized in other comprehensive income 740 720 546 Total recognized in net periodic benefit cost and other comprehensive income $ 168 $ 79 $ (172 ) Weighted average assumptions used to determine net periodic benefit cost Discount rate 3.7 % 4.2 % 4.5 % Health care cost trend rate: Initial rate 7.0 % 7.0 % 6.5 % Ultimate rate 5.0 % 5.0 % 5.0 % Years to ultimate 2022 2021 2019 Effect of one-percentage-point change in assumed health care cost trend rate on aggregate service and interest cost Increase $ 3 $ 3 $ 4 Decrease (2 ) (3 ) (3 )
Estimated Amounts that will be Amortized from Accumulated Other Comprehensive Income into Net Periodic Benefit Cost	The estimated amounts that will be amortized from accumulated other comprehensive income into net periodic benefit cost in 2019 are as follows (in thousands): Other Postretirement Benefits Postretirement Welfare Plan Actuarial gain $ (540 ) Prior service cost — $ (540 )

Other Comprehensive Income (Tab

Other Comprehensive Income (Tables)	12 Months Ended
	Dec. 31, 2018
Other Comprehensive Income [Abstract]
Changes in Other Comprehensive Income	The Company’s changes in other comprehensive income for the years ended December 31, 2018, 2017 and 2016 were as follows (in thousands): 2018 2017 2016 Gross Amount Income Tax (Provision) Benefit Net Amount Gross Amount Income Tax (Provision) Benefit Net Amount Gross Amount Income Tax (Provision) Benefit Net Amount Pension and postretirement benefits (a): Amortization of net actuarial loss $ 2,317 $ (585 ) $ 1,732 $ 3,760 $ (1,417 ) $ 2,343 $ 4,763 $ (1,825 ) $ 2,938 Actuarial gains (losses) 7,322 (1,416 ) 5,906 25,776 (9,371 ) 16,405 (15,013 ) 5,754 (9,259 ) Adoption of ASU 2018-02 – reclassification to retained earnings — (7,925 ) (7,925 ) — — — — — — Foreign currency translation adjustments (819 ) — (819 ) (146 ) — (146 ) — — — Total $ 8,820 $ (9,926 ) $ (1,106 ) $ 29,390 $ (10,788 ) $ 18,602 $ (10,250 ) $ 3,929 $ (6,321 ) (a) Actuarial gains (losses) are amortized into other income (expense). (See Note 11 – Retirement Plans)

Earnings Per Share (Tables)

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2018
Earnings Per Share [Abstract]
Earnings Per Share	The following table presents the components of basic and diluted earnings per share for the years ended December 31, 2018, 2017 and 2016 (in thousands, except per share amounts): 2018 2017 2016 Net earnings attributable to Kirby $ 78,452 $ 313,187 $ 141,406 Undistributed earnings allocated to restricted shares (324 ) (2,213 ) (999 ) Income available to Kirby common stockholders — basic 78,128 310,974 140,407 Undistributed earnings allocated to restricted shares 324 2,213 999 Undistributed earnings reallocated to restricted shares (323 ) (2,211 ) (997 ) Income available to Kirby common stockholders — diluted $ 78,129 $ 310,976 $ 140,409 Shares outstanding: Weighted average common stock issued and outstanding 59,804 55,702 53,834 Weighted average unvested restricted stock (247 ) (394 ) (380 ) Weighted average common stock outstanding — basic 59,557 55,308 53,454 Dilutive effect of stock options and restricted stock units 132 53 58 Weighted average common stock outstanding — diluted 59,689 55,361 53,512 Net earnings per share attributable to Kirby common stockholders: Basic $ 1.31 $ 5.62 $ 2.63 Diluted $ 1.31 $ 5.62 $ 2.62

Quarterly Results (Unaudited) (

Quarterly Results (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2018
Quarterly Results (Unaudited) [Abstract]
Quarterly Results	The unaudited quarterly results for the year ended December 31, 2018 were as follows (in thousands, except per share amounts): Three Months Ended March 31, 2018 June 30, 2018 September 30, 2018 December 31, 2018 Revenues $ 741,688 $ 802,671 $ 704,845 $ 721,493 Costs and expenses 692,866 747,260 636,906 740,344 Gain (loss) on disposition of assets 1,898 442 18 (390 ) Operating income (loss) 50,720 55,853 67,957 (19,241 ) Other income 1,591 1,541 1,454 1,140 Interest expense (9,780 ) (12,540 ) (12,345 ) (12,191 ) Earnings (loss) before taxes on income 42,531 44,854 57,066 (30,292 ) Benefit (provision) for taxes on income (9,865 ) (16,061 ) (15,116 ) 5,961 Net earnings (loss) 32,666 28,793 41,950 (24,331 ) Less: Net earnings attributable to noncontrolling interests (195 ) (191 ) (134 ) (106 ) Net earnings (loss) attributable to Kirby $ 32,471 $ 28,602 $ 41,816 $ (24,437 ) Net earnings (loss) per share attributable to Kirby common stockholders: Basic $ 0.54 $ 0.48 $ 0.70 $ (0.41 ) Diluted $ 0.54 $ 0.48 $ 0.70 $ (0.41 ) The unaudited quarterly results for the year ended December 31, 2017 were as follows (in thousands, except per share amounts): Three Months Ended March 31, 2017 June 30, 2017 September 30, 2017 December 31, 2017 Revenues $ 491,705 $ 473,328 $ 541,274 $ 708,111 Costs and expenses 445,760 425,937 488,186 756,423 Gain (loss) on disposition of assets 99 (139 ) (159 ) (4,288 ) Operating income (loss) 46,044 47,252 52,929 (52,600 ) Other income (expense) (589 ) 228 320 902 Interest expense (4,457 ) (4,465 ) (5,388 ) (7,162 ) Earnings (loss) before taxes on income 40,998 43,015 47,861 (58,860 ) Benefit (provision) for taxes on income (13,353 ) (17,043 ) (19,072 ) 290,357 Net earnings 27,645 25,972 28,789 231,497 Less: Net earnings attributable to noncontrolling interests (162 ) (194 ) (182 ) (178 ) Net earnings attributable to Kirby $ 27,483 $ 25,778 $ 28,607 $ 231,319 Net earnings per share attributable to Kirby common stockholders: Basic $ 0.51 $ 0.48 $ 0.52 $ 3.88 Diluted $ 0.51 $ 0.48 $ 0.52 $ 3.87

Segment Data (Tables)

Segment Data (Tables)	12 Months Ended
	Dec. 31, 2018
Segment Data [Abstract]
Segment Reporting Information, by Segment	The following table sets forth by reportable segment the revenues, profit or loss, total assets, depreciation and amortization, and capital expenditures attributable to the principal activities of the Company for the years ended December 31, 2018, 2017 and 2016 (in thousands): 2018 2017 2016 Revenues: Marine transportation $ 1,483,143 $ 1,324,106 $ 1,471,893 Distribution and services 1,487,554 890,312 298,780 $ 2,970,697 $ 2,214,418 $ 1,770,673 Segment profit (loss): Marine transportation $ 147,416 $ 135,547 $ 259,453 Distribution and services 129,305 86,479 3,068 Other (162,562 ) (149,012 ) (34,775 ) $ 114,159 $ 73,014 $ 227,746 Total assets: Marine transportation $ 4,145,294 $ 3,485,099 $ 3,613,951 Distribution and services 1,653,636 1,567,085 623,268 Other 72,664 75,243 52,676 $ 5,871,594 $ 5,127,427 $ 4,289,895 Depreciation and amortization: Marine transportation $ 182,307 $ 178,898 $ 184,291 Distribution and services 39,349 20,387 12,833 Other 3,316 3,596 3,793 $ 224,972 $ 202,881 $ 200,917 Capital expenditures: Marine transportation $ 284,953 $ 165,421 $ 217,423 Distribution and services 10,742 5,086 5,915 Other 6,166 6,715 7,728 $ 301,861 $ 177,222 $ 231,066
Other Segment Reporting Information	The following table presents the details of “Other” segment profit (loss) for the years ended December 31, 2018, 2017 and 2016 (in thousands): 2018 2017 2016 General corporate expenses $ (35,590 ) $ (18,202 ) $ (15,024 ) Interest expense (46,856 ) (21,472 ) (17,690 ) Impairment of long-lived assets (82,705 ) (105,712 ) — Impairment of goodwill (2,702 ) — — Lease cancellation costs (2,403 ) — — Gain (loss) on disposition of assets 1,968 (4,487 ) (127 ) Other income (expense) 5,726 861 (1,934 ) $ (162,562 ) $ (149,012 ) $ (34,775 ) The following table presents the details of “Other” total assets as of December 31, 2018, 2017 and 2016 (in thousands): 2018 2017 2016 General corporate assets $ 70,169 $ 73,353 $ 50,054 Investment in affiliates 2,495 1,890 2,622 $ 72,664 $ 75,243 $ 52,676

Summary of Significant Accoun_4

Summary of Significant Accounting Policies (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Accounts Receivable [Abstract]
Accruals for revenues earned included in accounts receivable	$ 114,159	$ 153,661
Receivables from insurance companies to cover claims in excess included in accounts receivable	$ 69,624	66,588
Drydocking on Ocean-Going Vessels [Abstract]
Period in which recertification of ocean going vessels occur twice	5 years
Recognized amortization of major maintenance costs	$ 20,760	21,207	$ 19,869
Capitalized interest excluded from interest expense	$ 2,206	$ 1,731	$ 2,974
Minimum [Member]
Drydocking on Ocean-Going Vessels [Abstract]
Period of amortization of shipyard costs	30 months
Maximum [Member]
Drydocking on Ocean-Going Vessels [Abstract]
Period of amortization of shipyard costs	60 months
Marine Transportation Equipment [Member] | Minimum [Member]
Property, Maintenance and Repairs [Abstract]
Estimated useful lives of the individual assets	5 years
Marine Transportation Equipment [Member] | Maximum [Member]
Property, Maintenance and Repairs [Abstract]
Estimated useful lives of the individual assets	40 years
Buildings [Member] | Minimum [Member]
Property, Maintenance and Repairs [Abstract]
Estimated useful lives of the individual assets	10 years
Buildings [Member] | Maximum [Member]
Property, Maintenance and Repairs [Abstract]
Estimated useful lives of the individual assets	40 years
Other Equipment [Member] | Minimum [Member]
Property, Maintenance and Repairs [Abstract]
Estimated useful lives of the individual assets	2 years
Other Equipment [Member] | Maximum [Member]
Property, Maintenance and Repairs [Abstract]
Estimated useful lives of the individual assets	10 years

Summary of Significant Accoun_5

Summary of Significant Accounting Policies, Goodwill and Other Intangibles (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Feb. 14, 2018
Goodwill [Abstract]
Impairment of goodwill	$ 2,702	$ 0	$ 0
Gross carrying value of goodwill	973,995	947,502
Accumulated amortization	15,566	15,566
Accumulated impairment losses	4,603	1,901
Net goodwill	953,826	935,135		$ 4,657
Other Intangibles [Abstract]
Intangible assets gross carrying amounts	326,984	315,983
Intangible assets accumulated amortization	102,787	83,175
Intangible assets net carrying amount	224,197	232,808
Intangible liabilities gross carrying value	18,323	7,437
Intangible liabilities accumulated amortization	8,652	4,751
Intangible liabilities net carrying amount	9,671	2,686
Amortization of intangible assets	16,760	11,296	$ 8,467
Intangible Assets and liabilities, Estimated Amortization Expense, Fiscal Year Maturity [Abstract]
2,018	18,999
2,019	20,854
2,020	20,174
2,021	19,824
2,022	$ 19,782
Weighted average amortization period for intangible assets and liabilities	14 years
Marine Transportation Segment [Member]
Goodwill [Abstract]
Net goodwill	$ 405,575	387,504
Distribution and Services Segment [Member]
Goodwill [Abstract]
Net goodwill	$ 548,251	$ 547,631

Summary of Significant Accoun_6

Summary of Significant Accounting Policies, Revenue Recognition through Accrued Insurance (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Accrued Insurance [Abstract]
Accrued insurance liabilities	$ 29,306	$ 26,195	$ 23,085
Marine Transportation Segment [Member] | Minimum [Member]
Revenue Recognition [Abstract]
Range of term contracts	1 year
Marine Transportation Segment [Member] | Maximum [Member]
Revenue Recognition [Abstract]
Range of term contracts	3 years

Summary of Significant Accoun_7

Summary of Significant Accounting Policies, Accounting Standards (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
New Accounting Pronouncements [Abstract]
Operating expense	$ (19,241)	$ 67,957	$ 55,853	$ 50,720	$ (52,600)	$ 52,929	$ 47,252	$ 46,044	$ 155,289	$ 93,625	$ 247,370
Nonoperating expense	(1,140)	(1,454)	(1,541)	(1,591)	(902)	(320)	(228)	589
Statements of earnings [Abstract]
Revenues									2,970,697	2,214,418	1,770,673
Costs of sales and operating expenses									2,160,946	1,558,098	1,124,666
Operating income	(19,241)	67,957	55,853	50,720	(52,600)	52,929	47,252	46,044	155,289	93,625	247,370
Earnings before taxes on income	(30,292)	57,066	44,854	42,531	(58,860)	47,861	43,015	40,998	114,159	73,014	227,746
Provision for taxes on income	5,961	(15,116)	(16,061)	(9,865)	290,357	(19,072)	(17,043)	(13,353)	(35,081)	240,889	(84,942)
Net earnings attributable to Kirby	(24,437)	41,816	28,602	32,471	231,319	28,607	25,778	27,483	78,452	313,187	141,406
Statements of comprehensive income [Abstract]
Net earnings	(24,331)	41,950	28,793	32,666	231,497	28,789	25,972	27,645	79,078	313,903	142,804
Comprehensive income attributable to Kirby									77,346	331,789	135,085
Statements of cash flows [Abstract]
Net earnings	(24,331)	$ 41,950	$ 28,793	$ 32,666	231,497	$ 28,789	$ 25,972	$ 27,645	79,078	313,903	142,804
Provision for deferred income taxes									34,881	(256,263)	51,296
Decrease in cash flows resulting from changes in: [Abstract]
Accounts receivable									12,511	(60,405)	(12,750)
Inventory									(144,685)	19,673	3,182
Accrued and other liabilities									30,712	(3,105)	16,051
Balance sheets [Abstract]
Trade receivables	417,644				452,222				417,644	452,222
Inventories - net	507,441				315,729				507,441	315,729
Total assets	5,871,594				5,127,427				5,871,594	5,127,427	4,289,895
Deferred revenues	80,123				48,347				80,123	48,347
Deferred income taxes	542,785				468,451				542,785	468,451
Retained earnings	2,723,592				2,646,937				2,723,592	2,646,937
Total liabilities and equity	5,871,594				5,127,427				5,871,594	5,127,427
Distribution and Services [Member]
Statements of earnings [Abstract]
Revenues									1,487,554	890,312	298,780
Retained Earnings [Member]
Statements of earnings [Abstract]
Net earnings attributable to Kirby									78,452	313,187	141,406
ASU 2016-09 [Member] | Retained Earnings [Member]
New Accounting Pronouncements [Abstract]
Cumulative effect on retained earnings					0					0	8,486	$ 0
ASU 2018-02 [Member] | Accumulated Other Comprehensive Income (Loss) [Member]
New Accounting Pronouncements [Abstract]
Cumulative effect on retained earnings					7,925					7,925	0	0
Reclassification from AOCI to retained earnings	(7,925)								(7,925)
ASU 2018-02 [Member] | Retained Earnings [Member]
New Accounting Pronouncements [Abstract]
Cumulative effect on retained earnings					(7,925)					(7,925)	0	0
Reclassification from AOCI to retained earnings	7,925								7,925
ASU 2017-07 [Member]
New Accounting Pronouncements [Abstract]
Operating expense										(621)	(2,175)
Nonoperating expense										(621)	(2,175)
Statements of earnings [Abstract]
Operating income										(621)	(2,175)
ASC 606 [Member]
New Accounting Pronouncements [Abstract]
Cumulative effect on retained earnings	(9,722)								(9,722)
ASC 606 [Member] | Balances without Adoption of ASC 606 [Member]
New Accounting Pronouncements [Abstract]
Operating expense									163,189
Statements of earnings [Abstract]
Costs of sales and operating expenses									2,181,046
Operating income									163,189
Earnings before taxes on income									122,059
Provision for taxes on income									(37,187)
Net earnings attributable to Kirby									84,246
Statements of comprehensive income [Abstract]
Net earnings									84,872
Comprehensive income attributable to Kirby									83,140
Statements of cash flows [Abstract]
Net earnings									84,872
Provision for deferred income taxes									32,775
Decrease in cash flows resulting from changes in: [Abstract]
Accounts receivable									(71,624)
Inventory									(71,985)
Accrued and other liabilities									38,459
Balance sheets [Abstract]
Trade receivables	501,779								501,779
Inventories - net	434,741								434,741
Total assets	5,883,029								5,883,029
Deferred revenues	70,858								70,858
Deferred income taxes	547,991								547,991
Retained earnings	2,739,086								2,739,086
Total liabilities and equity	5,883,029								5,883,029
ASC 606 [Member] | Balances without Adoption of ASC 606 [Member] | Distribution and Services [Member]
Statements of earnings [Abstract]
Revenues									1,515,554
ASC 606 [Member] | Effect of Change [Member]
New Accounting Pronouncements [Abstract]
Operating expense									(7,900)
Statements of earnings [Abstract]
Costs of sales and operating expenses									(20,100)
Operating income									(7,900)
Earnings before taxes on income									(7,900)
Provision for taxes on income									2,106
Net earnings attributable to Kirby									(5,794)
Statements of comprehensive income [Abstract]
Net earnings									(5,794)
Comprehensive income attributable to Kirby									(5,794)
Statements of cash flows [Abstract]
Net earnings									(5,794)
Provision for deferred income taxes									2,106
Decrease in cash flows resulting from changes in: [Abstract]
Accounts receivable									84,135
Inventory									(72,700)
Accrued and other liabilities									(7,747)
Balance sheets [Abstract]
Trade receivables	(84,135)								(84,135)
Inventories - net	72,700								72,700
Total assets	(11,435)								(11,435)
Deferred revenues	9,265								9,265
Deferred income taxes	(5,206)								(5,206)
Retained earnings	(15,494)								(15,494)
Total liabilities and equity	(11,435)								(11,435)
ASC 606 [Member] | Effect of Change [Member] | Distribution and Services [Member]
Statements of earnings [Abstract]
Revenues									(28,000)
ASC 606 [Member] | Retained Earnings [Member]
New Accounting Pronouncements [Abstract]
Cumulative effect on retained earnings	(9,722)				$ 9,722				(9,722)	$ 9,722	$ 0	$ 0
ASU 2016-02 [Member]
New Accounting Pronouncements [Abstract]
Right-of-use assets	185,000								185,000
Liabilities for operating leases	$ 180,000								$ 180,000

Revenues (Details)

Revenues (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Disaggregation of Revenue [Abstract]
Revenues by major source	$ 2,970,697	$ 2,214,418	$ 1,770,673
Revenue recognized	43,348
Marine Transportation [Member]
Disaggregation of Revenue [Abstract]
Revenues by major source	1,483,143	1,324,106	1,471,893
Marine Transportation [Member] | Inland Transportation [Member]
Disaggregation of Revenue [Abstract]
Revenues by major source	1,119,820	923,916	951,097
Marine Transportation [Member] | Coastal Transportation [Member]
Disaggregation of Revenue [Abstract]
Revenues by major source	363,323	400,190	520,796
Distribution and Services [Member]
Disaggregation of Revenue [Abstract]
Revenues by major source	1,487,554	890,312	298,780
Distribution and Services [Member] | Oil and Gas [Member]
Disaggregation of Revenue [Abstract]
Revenues by major source	1,010,410	614,128	115,012
Distribution and Services [Member] | Commercial and Industrial [Member]
Disaggregation of Revenue [Abstract]
Revenues by major source	$ 477,144	$ 276,184	$ 183,768

Revenues, Remaining Performance

Revenues, Remaining Performance Obligation (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Revenue, Performance Obligation [Abstract]
Contract assets	$ 0	$ 0
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-01-01
Revenue, Performance Obligation [Abstract]
Expected timing of satisfaction, period	1 year
Remaining performance obligation	$ 80,123

Acquisitions, 2018 (Details)

Acquisitions, 2018 (Details) $ in Thousands	Dec. 28, 2018USD ($)TankBarge	Dec. 14, 2018USD ($)TankBargebbl	Nov. 30, 2018USD ($)Towboat	May 10, 2018USD ($)TankBargebbl	Mar. 15, 2018USD ($)TankBarge	Feb. 14, 2018USD ($)bblTankBargeTowboat	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Acquisitions [Abstract]
Purchase price							$ 301,861	$ 177,222	$ 231,066
Assets [Abstract]
Cash						$ 2,313
Accounts receivable						27,527
Prepaid expenses and other current assets						5,323
Property and equipment						497,951
Goodwill						4,657	953,826	$ 935,135
Other assets						30
Total assets						537,801
Liabilities [Abstract]
Accounts payable						17,012
Accrued liabilities						14,127
Deferred revenues						40,524
Other long-term liabilities						44,216
Total liabilities						115,879
Net assets acquired						421,922
Senior Notes Due March 1, 2028 [Member]
Acquisitions [Abstract]
Long term debt, face amount							$ 500,000
Debt instrument, interest rate							4.20%
Maturity Date							Mar. 1, 2028
Inland Tank Barges [Member]
Acquisitions [Abstract]
Purchase price	$ 3,120	$ 28,500
Number of maritime vessels acquired | TankBarge	3	27
Tank barge barrel capacity (in barrels) | bbl		306,000
Average age of property		8 years
Inland Towboats [Member]
Acquisitions [Abstract]
Purchase price			$ 3,050
Number of maritime vessels acquired | Towboat			1
Inland Pressure Tank Barges [Member]
Acquisitions [Abstract]
Purchase price					$ 10,400
Number of maritime vessels acquired | TankBarge					2
Average age of property					5 years
Targa [Member]
Acquisitions [Abstract]
Cash paid for acquisition				$ 69,250
Goodwill acquired				16,116
Intangible assets acquired				$ 11,000
Weighted average amortization period of intangibles				15 years
Targa [Member] | Inland Pressure Tank Barges [Member]
Acquisitions [Abstract]
Number of maritime vessels acquired | TankBarge				16
Tank barge barrel capacity (in barrels) | bbl				258,000
Average age of property				15 years
Higman [Member]
Acquisitions [Abstract]
Cash paid for acquisition						421,922
Goodwill acquired						4,657
Intangible assets acquired						$ 11,100
Weighted average amortization period of intangibles						4 years 10 months 24 days
Acquisition related costs						$ 3,464
Higman [Member] | Senior Notes Due March 1, 2028 [Member]
Acquisitions [Abstract]
Long term debt, face amount						$ 500,000
Debt instrument, interest rate						4.20%
Maturity Date						Mar. 1, 2028
Higman [Member] | Inland Tank Barges [Member]
Acquisitions [Abstract]
Number of maritime vessels acquired | TankBarge						163
Aggregate tank barge barrel capacity (in barrels) | bbl						4,800,000
Average age of property						7 years
Higman [Member] | Inland Towboats [Member]
Acquisitions [Abstract]
Number of maritime vessels acquired | Towboat						75
Average age of property						8 years

Acquisitions, 2017 (Details)

Acquisitions, 2017 (Details) $ / shares in Units, $ in Thousands

Dec. 28, 2018USD ($)TankBarge

Dec. 14, 2018USD ($)TankBargebbl

Nov. 30, 2018USD ($)Towboat

Mar. 15, 2018USD ($)TankBarge

Oct. 20, 2017USD ($)

Sep. 13, 2017USD ($)BranchState$ / sharesshares

Jul. 10, 2017USD ($)TankBargeTowboatbblhp

Jul. 31, 2017USD ($)TankBarge

Dec. 31, 2018USD ($)

Dec. 31, 2017USD ($)

Dec. 31, 2016USD ($)

Feb. 14, 2018USD ($)

Jun. 25, 2017USD ($)

Acquisitions [Abstract]

Purchase price

$ 301,861

$ 177,222

$ 231,066

Property acquired

$ 497,951

Revolving Credit Facility [Member]

Acquisitions [Abstract]

Maximum borrowing capacity

$ 850,000

Maturity date

Jun. 26, 2022

Inland Pressure Tank Barges [Member]

Acquisitions [Abstract]

Purchase price

$ 10,400

Number of maritime vessels acquired | TankBarge

2

Average age of property

5 years

Inland Towboats [Member]

Acquisitions [Abstract]

Purchase price

$ 3,050

Number of maritime vessels acquired | Towboat

1

Inland Tank Barges [Member]

Acquisitions [Abstract]

Purchase price

$ 3,120

$ 28,500

Number of maritime vessels acquired | TankBarge

3

27

Tank barge barrel capacity (in barrels) | bbl

306,000

Average age of property

8 years

Sneed Shipbuilding, Inc [Member]

Acquisitions [Abstract]

Cash paid for acquisition

$ 14,852

Stewart & Stevenson LLC [Member]

Acquisitions [Abstract]

Cash paid for acquisition

$ 377,935

Purchase price before post-closing adjustment and transaction fees

758,213

Assumption of debt

13,724

Stock consideration through issuance of Company common stock

$ 366,554

Issuance of shares (in shares) | shares

5,696,259

Price per share (in dollars per share) | $ / shares

$ 64.35

Term debt assumed

$ 12,135

Short-term secured loans

$ 1,589

Number of branches | Branch

40

Number of states having branches | State

12

Stewart & Stevenson LLC [Member] | Revolving Credit Facility [Member]

Acquisitions [Abstract]

Maximum borrowing capacity

$ 850,000

$ 550,000

Maturity date

Jun. 26, 2022

Undisclosed Competitor [Member]

Acquisitions [Abstract]

Purchase price

$ 68,000

Property acquired

67,970

Intangible assets acquired

$ 30

Weighted average amortization period of intangibles

2 years

Undisclosed Competitor [Member] | Inland Pressure Tank Barges [Member]

Acquisitions [Abstract]

Number of maritime vessels acquired | TankBarge

9

Undisclosed Competitor [Member] | Barrel Tank Barges [Member]

Acquisitions [Abstract]

Number of maritime vessels acquired | TankBarge

4

Tank barge barrel capacity (in barrels) | bbl

30,000

Undisclosed Competitor [Member] | Inland Towboats [Member]

Acquisitions [Abstract]

Number of maritime vessels acquired | Towboat

3

Horsepower of inland towboats | hp

1,320

Undisclosed Competitor [Member] | Inland Tank Barges [Member]

Acquisitions [Abstract]

Number of maritime vessels acquired | TankBarge

13

Average age of property

5 years

Barge Fleeting and Marine Fueling Operation Business [Member]

Acquisitions [Abstract]

Cash paid for acquisition

$ 3,900

Barge Fleeting and Marine Fueling Operation Business [Member] | Inland Tank Barges [Member]

Acquisitions [Abstract]

Purchase price

$ 1,450

Number of maritime vessels acquired | TankBarge

4

Acquisitions, 2016 (Details)

Acquisitions, 2016 (Details) $ in Thousands	Dec. 28, 2018USD ($)TankBarge	Dec. 14, 2018USD ($)TankBargebbl	Nov. 30, 2018USD ($)Towboat	Oct. 11, 2016USD ($)State	Jun. 30, 2016USD ($)TankBargebbl	Jun. 02, 2016USD ($)Tugboat	Apr. 15, 2016USD ($)TankBargeTowboatbbl	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Acquisitions [Abstract]
Purchase price								$ 301,861	$ 177,222	$ 231,066
Inland Tank Barges [Member]
Acquisitions [Abstract]
Purchase price	$ 3,120	$ 28,500
Number of maritime vessels acquired | TankBarge	3	27
Tank barge barrel capacity (in barrels) | bbl		306,000
Average age of property		8 years
Inland Towboats [Member]
Acquisitions [Abstract]
Purchase price			$ 3,050
Number of maritime vessels acquired | Towboat			1
Valley Power Systems Northwest, Inc. [Member]
Acquisitions [Abstract]
Purchase price				$ 11,440
Goodwill acquired				8,330
Intangible assets acquired				$ 2,070
Weighted average amortization period of intangibles				15 years
Number of western states included in distributor agreement | State				9
TD Equipment Finance, Inc. [Member] | Coastal Tank Barge [Member]
Acquisitions [Abstract]
Purchase price					$ 13,682
Number of maritime vessels acquired | TankBarge					1
Tank barge barrel capacity (in barrels) | bbl					80,000
Crosby Marine Transportation LLC [Member] | Coastal Tugboats [Member]
Acquisitions [Abstract]
Purchase price						$ 26,450
Number of maritime vessels acquired | Tugboat						4
Average age of property						13 years
SEACOR Holdings Inc. [Member]
Acquisitions [Abstract]
Purchase price							$ 89,181
Cash paid for acquisition							85,500
Ownership transferred, value							3,681
Goodwill acquired							985
Intangible assets acquired							$ 0
SEACOR Holdings Inc. [Member] | Inland Tank Barges [Member]
Acquisitions [Abstract]
Number of maritime vessels acquired | TankBarge							27
Tank barge barrel capacity (in barrels) | bbl							30,000
Average age of property							10 years
SEACOR Holdings Inc. [Member] | Inland Towboats [Member]
Acquisitions [Abstract]
Number of maritime vessels acquired | Towboat							14

Acquisitions, Pro Forma (Detail

Acquisitions, Pro Forma (Details) - Stewart & Stevenson LLC [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Pro Forma [Abstract]
Revenues	$ 2,556,131	$ 2,299,800
Net earnings attributable to parent	$ 303,097	$ 125,197

Impairment of Long-lived Asse_2

Impairment of Long-lived Assets (Details) $ / shares in Units, $ in Thousands	3 Months Ended		12 Months Ended
	Dec. 31, 2018USD ($)$ / shares	Dec. 31, 2017USD ($)$ / shares	Dec. 31, 2018USD ($)TankBarge	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Long-lived Assets Impairment [Abstract]
Non-cash pre-tax impairment charge	$ 82,705	$ 105,712	$ 82,705	$ 105,712	$ 0
Impairment charge after tax effect	$ 65,337	$ 66,975
Impairment charge after tax effect on earning per share (in dollars per share) | $ / shares	$ 1.09	$ 1.20
Lease cancellation costs			2,403	0	$ 0
Vessels [Member]
Long-lived Assets Impairment [Abstract]
Non-cash pre-tax impairment charge	$ 78,835
Fair market value of assets	13,247	$ 12,550	13,247	$ 12,550
Tank Barge [Member]
Long-lived Assets Impairment [Abstract]
Non-cash pre-tax impairment charge			$ 3,870
Number of vessels to be disposed of | TankBarge			4
Fair market value of assets	220		$ 220
Scrap value of vessel	$ 220		220
Lease cancellation costs			$ 2,403

Inventories (Details)

Inventories (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Details of inventories [Abstract]
Finished goods	$ 406,364	$ 242,333
Work in process	101,077	73,396
Inventory, Net, Total	$ 507,441	$ 315,729

Fair Value Measurements (Detail

Fair Value Measurements (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Vessels [Member]
Fair Value Measurements [Abstract]
Fair market value of assets	$ 13,247	$ 12,550
Nonrecurring Basis [Member] | Prepaid Expenses and Other Current Assets [Member]
Fair Value Measurements [Abstract]
Fair market value of assets	220
Nonrecurring Basis [Member] | Vessels [Member]
Fair Value Measurements [Abstract]
Fair market value of assets	13,467
Nonrecurring Basis [Member] | Marine Transportation Equipment [Member]
Fair Value Measurements [Abstract]
Fair market value of assets	$ 13,247

Long-Term Debt, Schedule of Lon

Long-Term Debt, Schedule of Long-Term Debt (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Long-term debt [Abstract]
Long-term Debt	$ 1,417,392	$ 995,848
Unamortized debt issuance costs	(6,550)	(3,442)
Unamortized debt discount	(654)	0
Total	1,410,188	992,406
Bank Notes Payable [Member]
Long-term debt [Abstract]
Long-term Debt	19	3
Revolving Credit Facility Due June 26, 2022 [Member]
Long-term debt [Abstract]
Long-term Debt	$ 417,373	495,845
Credit facility, expiration date	Jun. 26, 2022
Long term debt, face amount	$ 850,000
Senior Notes Series A Due February 27, 2020 [Member]
Long-term debt [Abstract]
Long-term Debt	$ 150,000	150,000
Debt maturity date	Feb. 27, 2020
Long term debt, face amount	$ 150,000
Senior Notes Series B Due February 27, 2023 [Member]
Long-term debt [Abstract]
Long-term Debt	$ 350,000	350,000
Debt maturity date	Feb. 27, 2023
Long term debt, face amount	$ 350,000
Senior Notes Due March 1, 2028 [Member]
Long-term debt [Abstract]
Long-term Debt	$ 500,000	0
Debt maturity date	Mar. 1, 2028
Long term debt, face amount	$ 500,000
Credit Line Due June 30, 2019 [Member]
Long-term debt [Abstract]
Long-term Debt	$ 0	$ 0
Credit facility, expiration date	Jun. 30, 2019
Long term debt, face amount	$ 10,000
Revolving Credit Facility [Member]
Long-term debt [Abstract]
Credit facility, expiration date	Jun. 26, 2022

Long-Term Debt, Schedule of Agg

Long-Term Debt, Schedule of Aggregate Payments Due on The Long-Term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Long-Term Debt [Abstract]
2,019	$ 19
2,020	150,000
2,021	0
2,022	417,373
2,023	350,000
Thereafter	500,000
Long-term Debt	$ 1,417,392	$ 995,848

Long-Term Debt (Details)

Long-Term Debt (Details) - USD ($) $ in Thousands	Feb. 20, 2018	Sep. 13, 2017	Dec. 31, 2018	Dec. 31, 2017	Jun. 25, 2017
Long-term Debt [Abstract]
Senior Notes outstanding			$ 1,417,392	$ 995,848
Total debt outstanding, Fair value			1,411,628	984,017
Long-term debt			1,410,188	992,406
Senior Notes Due March 1, 2028 [Member]
Long-term Debt [Abstract]
Long term debt, face amount			500,000
Periodic payment, interest			10,500
Periodic payment, interest, exception of first payment			11,608
Cash proceeds received			495,019
Original issue discount			705
Debt issuance costs			4,276
Senior Notes outstanding			$ 500,000	0
Debt instrument, interest rate, stated percentage			4.20%
Maturity Date			Mar. 1, 2028
Senior Notes Series A Due February 27, 2020 [Member]
Long-term Debt [Abstract]
Long term debt, face amount			$ 150,000
Senior Notes outstanding			$ 150,000	150,000
Debt instrument, interest rate, stated percentage			2.72%
Maturity Date			Feb. 27, 2020
Senior Notes Series B Due February 27, 2023 [Member]
Long-term Debt [Abstract]
Long term debt, face amount			$ 350,000
Senior Notes outstanding			$ 350,000	$ 350,000
Debt instrument, interest rate, stated percentage			3.29%
Maturity Date			Feb. 27, 2023
Term Loan Due September 15, 2032 [Member] | Stewart & Stevenson LLC [Member]
Long-term Debt [Abstract]
Term debt assumed, paid off		$ 12,135
Revolving Credit Facility [Member]
Long-term Debt [Abstract]
Maximum borrowing capacity			$ 850,000
Credit facility, expiration date			Jun. 26, 2022
Line of credit, increase in aggregate commitments			$ 300,000
Commitment amount			$ 25,000
Commitment fee	0.10%		0.15%
Credit facility, amount outstanding			$ 417,373
Average borrowing under revolving credit facility			$ 411,613
Weighted average interest rate			3.10%
Revolving Credit Facility [Member] | Stewart & Stevenson LLC [Member]
Long-term Debt [Abstract]
Maximum borrowing capacity			$ 850,000		$ 550,000
Credit facility, expiration date			Jun. 26, 2022
Revolving Credit Facility [Member] | LIBOR [Member]
Long-term Debt [Abstract]
Basis spread on variable rate	1.00%		1.125%
Revolving Credit Facility [Member] | Alternate Base Rate [Member]
Long-term Debt [Abstract]
Basis spread on variable rate			0.125%
Letter of Credit [Member]
Long-term Debt [Abstract]
Credit facility, amount outstanding			$ 6,788
Senior Notes [Member]
Long-term Debt [Abstract]
Long term debt, face amount			500,000
Line Of Credit [Member]
Long-term Debt [Abstract]
Maximum borrowing capacity			$ 10,000
Credit facility, expiration date			Jun. 30, 2019
Credit facility, amount outstanding			$ 1,171
Secured Debt [Member]
Long-term Debt [Abstract]
Short-term debt			$ 19,000

Taxes on Income, Earnings Befor

Taxes on Income, Earnings Before Taxes (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Earnings (loss) before taxes on income [Abstract]
Earnings (loss) before taxes on income	$ (30,292)	$ 57,066	$ 44,854	$ 42,531	$ (58,860)	$ 47,861	$ 43,015	$ 40,998	$ 114,159	$ 73,014	$ 227,746
U.S. Federal [Abstract]
Current									0	11,143	28,919
Deferred									27,102	(258,703)	49,685
Total U.S. Federal									27,102	(247,560)	78,604
U.S. State [Abstract]
Current									(243)	3,861	4,727
Deferred									7,619	2,280	1,611
Total U.S. State									7,376	6,141	6,338
Foreign [Abstract]
Current									443	370	0
Deferred									160	160	0
Total Foreign									603	530	0
Consolidated [Abstract]
Current									200	15,374	33,646
Deferred									34,881	(256,263)	51,296
Total Provision (benefit) for taxes on income	$ (5,961)	$ 15,116	$ 16,061	$ 9,865	$ (290,357)	$ 19,072	$ 17,043	$ 13,353	35,081	(240,889)	84,942
United States [Member]
Earnings (loss) before taxes on income [Abstract]
Earnings (loss) before taxes on income									117,800	74,267	227,746
Foreign [Member]
Earnings (loss) before taxes on income [Abstract]
Earnings (loss) before taxes on income									$ (3,641)	$ (1,253)	$ 0

Taxes on Income, Schedule of Ef

Taxes on Income, Schedule of Effective Income Tax Rate Reconciliation (Details)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Company's provision for taxes on income varied from the statutory federal income tax rate [Abstract]
United States income tax statutory rate	21.00%	35.00%	35.00%
State and local taxes, net of federal benefit	6.50%	0.90%	1.80%
Change due to U.S. tax reform	0.00%	(369.00%)	0.00%
Other - net	3.20%	3.20%	0.50%
Effective income tax rate	30.70%	(329.90%)	37.30%

Taxes on Income, Schedule of De

Taxes on Income, Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Deferred tax assets [Abstract]
Allowance for doubtful accounts	$ 2,105	$ 1,875
Inventory	5,017	3,795
Insurance accruals	4,119	4,599
Deferred compensation	1,291	1,849
Unrealized loss on defined benefit plans	9,891	11,097
Operating loss carryforwards	81,867	15,540
Pension benefits	6,559	549
Other	22,421	16,301
Deferred tax assets, gross	133,270	55,605
Valuation allowances	(25,568)	(15,308)
Deferred tax assets, net of valuation allowance	107,702	40,297
Deferred tax liabilities [Abstract]
Property	(526,873)	(428,947)
Deferred state taxes	(74,638)	(58,366)
Goodwill and other intangibles	(34,235)	(9,015)
Other	(14,741)	(12,420)
Deferred tax liabilities	(650,487)	(508,748)
Net deferred tax liabilities	(542,785)	(468,451)
Operating Loss Carryforward [Abstract]
Deferred tax assets	18,922
Historical net operating loss inherited amount	35,133
State operating loss deferred tax assets	19,039	9,289
Operating loss carryforwards, net of valuation allowance	$ 17,027	$ 9,289
Expiration dates, operating loss carryforwards	Dec. 31, 2037
Unrecognized tax benefits including interest and penalties	$ 1,909
Amount that would impact the effective tax rate, if recognized	1,182
Canada [Member]
Operating Loss Carryforward [Abstract]
Operating loss carryforwards	$ 8,541
Expiration dates, operating loss carryforwards	Dec. 31, 2038
State and Local Jurisdiction [Member] | Minimum [Member]
Open Tax Year [Abstract]
Years open to audit under the statute of limitations	2,012
State and Local Jurisdiction [Member] | Maximum [Member]
Open Tax Year [Abstract]
Years open to audit under the statute of limitations	2,017
Internal Revenue Service (IRS) [Member] | Minimum [Member]
Open Tax Year [Abstract]
Years open to audit under the statute of limitations	2,015
Internal Revenue Service (IRS) [Member] | Maximum [Member]
Open Tax Year [Abstract]
Years open to audit under the statute of limitations	2,017

Taxes on Income, Reconciliation

Taxes on Income, Reconciliation of Liability for Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Reconciliation of the beginning and ending amount of the liability for unrecognized tax benefits [Roll Forward]
Balance at beginning of year	$ 1,787	$ 2,019	$ 1,958
Additions based on tax positions related to the current year	254	403	187
Additions for tax positions of prior years	70	273	867
Reductions for tax positions of prior years	(668)	(908)	(441)
Settlements	0	0	(552)
Balance at end of year	1,443	1,787	2,019
Income tax penalties and interest recognized	209	120	88
Accrued liabilities for payment of interest and penalties	$ 466	$ 675	$ 554

Leases, Schedule of Rent Expens

Leases, Schedule of Rent Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Rental expense [Abstract]
Rental expense	$ 173,988	$ 144,155	$ 162,582
Other Buildings and Equipment [Member]
Rental expense [Abstract]
Rental expense	23,365	15,915	11,182
Barges [Member] | Marine Equipment [Member]
Rental expense [Abstract]
Rental expense	$ 10,234	11,550	13,791
Towing Vessels [Member]
Lease Agreements [Abstract]
Percentage of charter agreement for terms of one year or less	75.00%
Towing Vessels [Member] | Marine Equipment [Member]
Rental expense [Abstract]
Rental expense	$ 140,389	$ 116,690	$ 137,609
Minimum [Member] | Barges [Member]
Lease Agreements [Abstract]
Lease agreements expiring terms	1 year
Minimum [Member] | Towing Vessels [Member]
Lease Agreements [Abstract]
Lease agreements expiring terms	30 days
Maximum [Member] | Barges [Member]
Lease Agreements [Abstract]
Lease agreements expiring terms	12 years
Maximum [Member] | Towing Vessels [Member]
Lease Agreements [Abstract]
Lease agreements expiring terms	10 years

Leases, Schedule of Future Mini

Leases, Schedule of Future Minimum Lease Payments Under Operating Leases (Details) $ in Thousands	Dec. 31, 2018USD ($)
Future Minimum Lease Payments under Operating Leases [Abstract]
2,019	$ 97,091
2,020	30,062
2,021	21,818
2,022	20,263
2,023	17,429
Thereafter	91,939
Future minimum lease payments under operating leases	278,602
Marine Equipment [Member] | Barges [Member]
Future Minimum Lease Payments under Operating Leases [Abstract]
2,019	6,808
2,020	5,400
2,021	4,128
2,022	4,138
2,023	3,030
Thereafter	7,098
Future minimum lease payments under operating leases	30,602
Marine Equipment [Member] | Towing Vessels [Member]
Future Minimum Lease Payments under Operating Leases [Abstract]
2,019	70,759
2,020	7,746
2,021	2,578
2,022	2,578
2,023	2,578
Thereafter	9,023
Future minimum lease payments under operating leases	95,262
Land Buildings and Equipment [Member]
Future Minimum Lease Payments under Operating Leases [Abstract]
2,019	19,524
2,020	16,916
2,021	15,112
2,022	13,547
2,023	11,821
Thereafter	75,818
Future minimum lease payments under operating leases	$ 152,738

Stock Award Plans, Compensation

Stock Award Plans, Compensation Cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Stock Award Plans [Abstract]
Compensation cost	$ 19,104	$ 11,460	$ 11,675
Income tax benefit	$ 5,903	$ 4,333	$ 4,378

Stock Award Plans, Employee Pla

Stock Award Plans, Employee Plan Stock Option Activity (Details) - Employee Stock Award Plan [Member] - $ / shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Stock Award Plan Information [Abstract]
Shares available for future grants (in shares)	1,575,948
Stock Options [Member]
Stock Award Plan Information [Abstract]
Term of grant	7 years
Vesting period	3 years
Outstanding Non-Qualified or Nonincentive Stock Awards [Roll Forward]
Outstanding at Period Start (in shares)	654,655	601,121	430,432
Granted (in shares)	115,797	123,141	186,706
Exercised (in shares)	(283,886)	(36,616)
Forfeited (in shares)	(21,864)	(32,991)	(16,017)
Outstanding at Period End (in shares)	464,702	654,655	601,121
Weighted Average Exercise Price [Abstract]
Outstanding at Period Start (in dollars per share)	$ 66.45	$ 65.33	$ 71.01
Granted (in dollars per share)	75.50	68.46	53.50
Exercised (in dollars per share)	61.81	47.95
Forfeited (in dollars per share)	102.42	74.07	80.17
Outstanding at Period End (in dollars per share)	$ 69.85	$ 66.45	$ 65.33
Stock options exercisable (in shares)	230,254	380,608	321,942
Stock Appreciation Rights [Member]
Outstanding Non-Qualified or Nonincentive Stock Awards [Roll Forward]
Outstanding at Period End (in shares)	0

Stock Award Plans, Employee P_2

Stock Award Plans, Employee Plan Outstanding and Exercisable Options (Details) - Employee Stock Award Plan [Member] - Stock Options [Member]	12 Months Ended
	Dec. 31, 2018USD ($)$ / sharesshares
First Price Range [Member]
Outstanding and Exercisable Stock options [Abstract]
Range of Exercise Prices, upper limit (in dollars per share)	$ 51.23
Options Outstanding [Abstract]
Number Outstanding (in shares) | shares	90,975
Weighted Average Remaining Contractual Life	4 years 1 month 6 days
Weighted Average Exercise Price, Options Outstanding (in dollars per share)	$ 51.23
Options Exercisable [Abstract]
Number Exercisable (in shares) | shares	57,438
Weighted Average Exercise Price, Options Exercisable (in dollars per share)	$ 51.23
Second Price Range [Member]
Outstanding and Exercisable Stock options [Abstract]
Range of Exercise Prices, lower limit (in dollars per share)	64.65
Range of Exercise Prices, upper limit (in dollars per share)	$ 68.50
Options Outstanding [Abstract]
Number Outstanding (in shares) | shares	126,260
Weighted Average Remaining Contractual Life	4 years 8 months 12 days
Weighted Average Exercise Price, Options Outstanding (in dollars per share)	$ 67.23
Options Exercisable [Abstract]
Number Exercisable (in shares) | shares	41,146
Weighted Average Exercise Price, Options Exercisable (in dollars per share)	$ 67.40
Third Price Range [Member]
Outstanding and Exercisable Stock options [Abstract]
Range of Exercise Prices, lower limit (in dollars per share)	70.65
Range of Exercise Prices, upper limit (in dollars per share)	$ 75.50
Options Outstanding [Abstract]
Number Outstanding (in shares) | shares	207,156
Weighted Average Remaining Contractual Life	4 years 6 months
Weighted Average Exercise Price, Options Outstanding (in dollars per share)	$ 74.56
Options Exercisable [Abstract]
Number Exercisable (in shares) | shares	91,359
Weighted Average Exercise Price, Options Exercisable (in dollars per share)	$ 73.36
Fourth Price Range [Member]
Outstanding and Exercisable Stock options [Abstract]
Range of Exercise Prices, lower limit (in dollars per share)	93.64
Range of Exercise Prices, upper limit (in dollars per share)	$ 101.46
Options Outstanding [Abstract]
Number Outstanding (in shares) | shares	40,311
Weighted Average Remaining Contractual Life	2 years 1 month 6 days
Weighted Average Exercise Price, Options Outstanding (in dollars per share)	$ 95.90
Options Exercisable [Abstract]
Number Exercisable (in shares) | shares	40,311
Weighted Average Exercise Price, Options Exercisable (in dollars per share)	$ 95.90
Full Exercise Price Range [Member]
Outstanding and Exercisable Stock options [Abstract]
Range of Exercise Prices, lower limit (in dollars per share)	51.23
Range of Exercise Prices, upper limit (in dollars per share)	$ 101.46
Options Outstanding [Abstract]
Number Outstanding (in shares) | shares	464,702
Weighted Average Remaining Contractual Life	4 years 3 months 18 days
Weighted Average Exercise Price, Options Outstanding (in dollars per share)	$ 69.85
Aggregate Intrinsic Value, Options Outstanding | $	$ 1,570,000
Options Exercisable [Abstract]
Number Exercisable (in shares) | shares	230,254
Weighted Average Exercise Price, Options Exercisable (in dollars per share)	$ 70.72
Aggregate Intrinsic Value, Options Exercisable | $	$ 951,000

Stock Award Plans, Employee P_3

Stock Award Plans, Employee Plan Restricted Stock Award Activity (Details) - Employee Stock Award Plan [Member] - Restricted Stock [Member] - $ / shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Unvested RSU Shares [Roll Forward]
Nonvested balance beginning of period (in shares)	364,121	377,655	311,727
Granted (in shares)		127,255	190,610
Vested (in shares)	(144,265)	(105,600)	(105,109)
Forfeited (in shares)	(5,640)	(35,189)	(19,573)
Nonvested balance end of period (in shares)	214,216	364,121	377,655
Weighted Average Grant Date Fair Value Per Share [Abstract]
Nonvested balance beginning of period (in dollars per share)	$ 65.84	$ 66.14	$ 75.73
Granted (in dollars per share)		68.50	53.56
Vested (in dollars per share)	72.66	68.91	69.93
Forfeited (in dollars per share)	64.60	69.45	76.06
Nonvested balance end of period (in dollars per share)	$ 64.73	$ 65.84	$ 66.14

Stock Award Plans, Employee P_4

Stock Award Plans, Employee Plan RSU Activity (Details) - Employee Stock Award Plan [Member] - RSUs [Member]	12 Months Ended
	Dec. 31, 2018$ / sharesshares
Unvested RSU Shares [Roll Forward]
Nonvested balance beginning of period (in shares) | shares	0
Granted (in shares) | shares	143,890
Forfeited (in shares) | shares	(2,835)
Nonvested balance end of period (in shares) | shares	141,055
Weighted Average Grant Date Fair Value Per Share [Abstract]
Nonvested balance beginning of period (in dollars per share) | $ / shares	$ 0
Granted (in dollars per share) | $ / shares	75.59
Forfeited (in dollars per share) | $ / shares	75.50
Nonvested balance end of period (in dollars per share) | $ / shares	$ 75.59

Stock Award Plans, Director Pla

Stock Award Plans, Director Plan Stock Option Activity (Details) - Director Plan [Member] - $ / shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Stock Award Plan Information [Abstract]
Shares available for future grants (in shares)	486,058
Stock Options [Member]
Stock Award Plan Information [Abstract]
Term of grant	10 years
Outstanding Non-Qualified or Nonincentive Stock Awards [Roll Forward]
Outstanding at Period Start (in shares)	157,617	205,429	220,429
Granted (in shares)	2,640	3,188
Exercised (in shares)	(29,153)	(39,000)	(9,000)
Forfeited (in shares)		(12,000)	(6,000)
Outstanding at Period End (in shares)	131,104	157,617	205,429
Weighted Average Exercise Price [Abstract]
Outstanding at Period Start (in dollars per share)	$ 67.54	$ 64.60	$ 64.37
Granted (in dollars per share)	85.30	70.65
Exercised (in dollars per share)	57.47	46.23	35.72
Forfeited (in dollars per share)		87.35	99.52
Outstanding at Period End (in dollars per share)	$ 70.14	$ 67.54	$ 64.60
Stock options exercisable (in shares)	130,444	156,820	205,429
Restricted Stock [Member]
Stock Award Plan Information [Abstract]
Vesting period	6 months

Stock Award Plans, Director P_2

Stock Award Plans, Director Plan Outstanding and Exercisable Options (Details) - Director Plan [Member] - Stock Options [Member]	12 Months Ended
	Dec. 31, 2018USD ($)$ / sharesshares
First Price Range [Member]
Outstanding and Exercisable Stock options [Abstract]
Range of Exercise Prices, upper limit (in dollars per share)	$ 29.60
Options Outstanding [Abstract]
Number Outstanding (in shares) | shares	6,000
Weighted Average Remaining Contractual Life	3 months 18 days
Weighted Average Exercise Price, Options Outstanding (in dollars per share)	$ 29.6
Options Exercisable [Abstract]
Number Exercisable (in shares) | shares	6,000
Weighted Average Exercise Price, Options Exercisable (in dollars per share)	$ 29.60
Second Price Range [Member]
Outstanding and Exercisable Stock options [Abstract]
Range of Exercise Prices, lower limit (in dollars per share)	41.24
Range of Exercise Prices, upper limit (in dollars per share)	$ 56.45
Options Outstanding [Abstract]
Number Outstanding (in shares) | shares	31,276
Weighted Average Remaining Contractual Life	1 year 10 months 24 days
Weighted Average Exercise Price, Options Outstanding (in dollars per share)	$ 50.61
Options Exercisable [Abstract]
Number Exercisable (in shares) | shares	31,276
Weighted Average Exercise Price, Options Exercisable (in dollars per share)	$ 50.61
Third Price Range [Member]
Outstanding and Exercisable Stock options [Abstract]
Range of Exercise Prices, lower limit (in dollars per share)	61.89
Range of Exercise Prices, upper limit (in dollars per share)	$ 62.48
Options Outstanding [Abstract]
Number Outstanding (in shares) | shares	28,000
Weighted Average Remaining Contractual Life	3 years 7 months 6 days
Weighted Average Exercise Price, Options Outstanding (in dollars per share)	$ 62.27
Options Exercisable [Abstract]
Number Exercisable (in shares) | shares	28,000
Weighted Average Exercise Price, Options Exercisable (in dollars per share)	$ 62.27
Fourth Price Range [Member]
Outstanding and Exercisable Stock options [Abstract]
Range of Exercise Prices, lower limit (in dollars per share)	70.65
Range of Exercise Prices, upper limit (in dollars per share)	$ 99.52
Options Outstanding [Abstract]
Number Outstanding (in shares) | shares	65,828
Weighted Average Remaining Contractual Life	5 years 2 months 12 days
Weighted Average Exercise Price, Options Outstanding (in dollars per share)	$ 86.45
Options Exercisable [Abstract]
Number Exercisable (in shares) | shares	65,168
Weighted Average Exercise Price, Options Exercisable (in dollars per share)	$ 86.47
Full Exercise Price Range [Member]
Outstanding and Exercisable Stock options [Abstract]
Range of Exercise Prices, lower limit (in dollars per share)	29.60
Range of Exercise Prices, upper limit (in dollars per share)	$ 99.52
Options Outstanding [Abstract]
Number Outstanding (in shares) | shares	131,104
Weighted Average Remaining Contractual Life	3 years 9 months 18 days
Weighted Average Exercise Price, Options Outstanding (in dollars per share)	$ 70.14
Aggregate Intrinsic Value, Options Outstanding | $	$ 893,000
Options Exercisable [Abstract]
Number Exercisable (in shares) | shares	130,444
Weighted Average Exercise Price, Options Exercisable (in dollars per share)	$ 70.06
Aggregate Intrinsic Value, Options Exercisable | $	$ 893,000

Stock Award Plans, Director P_3

Stock Award Plans, Director Plan Restricted Stock Award Activity (Details) - Director Plan [Member] - Restricted Stock [Member] - $ / shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Unvested RSU Shares [Roll Forward]
Nonvested balance beginning of period (in shares)	347	1,791	292
Granted (in shares)	21,198	23,074	20,350
Vested (in shares)	(21,226)	(24,518)	(18,851)
Nonvested balance end of period (in shares)	319	347	1,791
Weighted Average Grant Date Fair Value Per Share [Abstract]
Nonvested balance beginning of period (in dollars per share)	$ 64.89	$ 68.73	$ 99.52
Granted (in dollars per share)	70.65	64.89	78.52
Vested (in dollars per share)	70.56	65.17	79.77
Nonvested balance end of period (in dollars per share)	$ 70.65	$ 64.89	$ 68.73

Stock Award Plans, All Plans Op

Stock Award Plans, All Plans Options and Restricted Stock Award Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Plans Combined Disclosure [Abstract]
Intrinsic value of stock options exercised	$ 6,709	$ 1,671	$ 266
Tax benefit from stock options exercised	2,073	632	100
Intrinsic value of restricted stock vesting	12,936	8,485	6,928
Tax benefit from restricted stock vesting	3,997	3,208	2,598
Fair value of options vested	3,191	2,530	2,495
Fair value of restricted stock vested	$ 12,936	$ 8,485	$ 6,928
Fair value of stock options granted (in dollars per share)	$ 23.53	$ 20.72	$ 17.30
Fair value of stock options granted	$ 2,787	$ 2,617	$ 3,231
Stock Options [Member]
Share-based Compensation Plans Combined Disclosure [Abstract]
Unrecognized compensation cost related to unvested awards	$ 2,294
Weighted average period of recognition in years	1 year 6 months
Fair Value Assumptions [Abstract]
Dividend yield	0.00%	0.00%	0.00%
Average risk-free interest rate	2.70%	2.00%	1.50%
Stock price volatility	27.00%	27.00%	30.00%
Estimated option term	6 years	6 years	6 years
Restricted Stock [Member]
Share-based Compensation Plans Combined Disclosure [Abstract]
Unrecognized compensation cost related to unvested awards	$ 8,647
Weighted average period of recognition in years	2 years 2 months 12 days
RSUs [Member]
Share-based Compensation Plans Combined Disclosure [Abstract]
Vesting (in shares)	0
Unrecognized compensation cost related to unvested awards	$ 5,732
Weighted average period of recognition in years	3 years 10 months 24 days

Retirement Plans, Information A

Retirement Plans, Information About Plan Assets and Asset Allocation (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Higman [Member]
Information about Plan Assets [Abstract]
Decrease in pension plan projected benefit obligation		$ (3,081)
Pension contributions	$ 6,717
Expected additional contribution		$ 1,385
Pension Plan [Member]
Information about Plan Assets [Abstract]
Service period of participants not impacted by pension plan amendment		15 years
Age of plan participants not impacted by pension plan amendment		50 years
Service period of participants who are age fifty not impacted by pension plan amendment		10 years
Decrease in pension plan projected benefit obligation		$ (33,433)
Pension contributions		8,102	$ 0
Expected additional contribution		2,395	0
Fair value of plan assets		$ 303,151	$ 294,995	$ 257,517
Expected long-term rate of return on plan assets		7.00%	7.00%	7.50%
Contribution percentage to defined contribution plan		85.00%
Asset Allocation Among Asset Categories [Abstract]
Asset allocations		100.00%	100.00%
Pension Plan [Member] | U.S. Equity Securities [Member]
Asset Allocation Among Asset Categories [Abstract]
Asset allocations		52.00%	51.00%
Target allocations		50.00%
Pension Plan [Member] | U.S. Equity Securities [Member] | Minimum [Member]
Asset Allocation Among Asset Categories [Abstract]
Target allocations		30.00%
Pension Plan [Member] | U.S. Equity Securities [Member] | Maximum [Member]
Asset Allocation Among Asset Categories [Abstract]
Target allocations		70.00%
Pension Plan [Member] | International Equity Securities [Member]
Asset Allocation Among Asset Categories [Abstract]
Asset allocations		17.00%	21.00%
Target allocations		20.00%
Pension Plan [Member] | International Equity Securities [Member] | Minimum [Member]
Asset Allocation Among Asset Categories [Abstract]
Target allocations		0.00%
Pension Plan [Member] | International Equity Securities [Member] | Maximum [Member]
Asset Allocation Among Asset Categories [Abstract]
Target allocations		30.00%
Pension Plan [Member] | Debt Securities [Member]
Asset Allocation Among Asset Categories [Abstract]
Asset allocations		28.00%	28.00%
Target allocations		30.00%
Pension Plan [Member] | Debt Securities [Member] | Minimum [Member]
Asset Allocation Among Asset Categories [Abstract]
Target allocations		15.00%
Pension Plan [Member] | Debt Securities [Member] | Maximum [Member]
Asset Allocation Among Asset Categories [Abstract]
Target allocations		55.00%
Pension Plan [Member] | Cash and Cash Equivalents [Member]
Asset Allocation Among Asset Categories [Abstract]
Asset allocations		3.00%	0.00%
Target allocations		0.00%
Pension Plan [Member] | Cash and Cash Equivalents [Member] | Minimum [Member]
Asset Allocation Among Asset Categories [Abstract]
Target allocations		0.00%
Pension Plan [Member] | Cash and Cash Equivalents [Member] | Maximum [Member]
Asset Allocation Among Asset Categories [Abstract]
Target allocations		5.00%
Other Postretirement Benefits [Member]
Information about Plan Assets [Abstract]
Pension contributions		$ 103	$ 75
Expected additional contribution		66	48
Fair value of plan assets		$ 0	$ 0	$ 0
Pension plan defined benefit plan cost increase limit percentage		4.00%

Retirement Plans, Schedule of C

Retirement Plans, Schedule of Change in Benefit Obligation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Pension Plan [Member]
Change in benefit obligation [Roll Forward]
Benefit obligation at beginning of year	$ 354,994	$ 337,176
Service cost	7,622	10,677	$ 13,402
Interest cost	15,499	13,729	14,123
Actuarial loss (gain)	(44,935)	34,563
Gross benefits paid	(11,749)	(7,718)
Curtailments	(3,081)	(33,433)
Acquisition	63,133	0
Benefit obligation at end of year	381,483	354,994	337,176
Accumulated benefit obligation at end of year	356,797	324,904
SERP [Member]
Change in benefit obligation [Roll Forward]
Benefit obligation at beginning of year	1,412	1,457
Service cost	0	0	0
Interest cost	49	58	65
Actuarial loss (gain)	(70)	42
Gross benefits paid	(145)	(145)
Curtailments	0	0
Acquisition	0	0
Benefit obligation at end of year	1,246	1,412	1,457
Accumulated benefit obligation at end of year	1,246	1,412
Other Postretirement Benefits [Member]
Change in benefit obligation [Roll Forward]
Benefit obligation at beginning of year	679	675
Service cost	0	0	0
Interest cost	24	27	29
Actuarial loss (gain)	143	52
Gross benefits paid	(103)	(75)
Curtailments	0	0
Acquisition	0	0
Benefit obligation at end of year	743	679	$ 675
Accumulated benefit obligation at end of year	$ 743	$ 679

Retirement Plans, Weighted-Aver

Retirement Plans, Weighted-Average Assumption Used to Determine Benefit Obligation (Details)		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Mar. 31, 2018	Feb. 14, 2018
Pension Plan [Member]
Weighted-average assumption used to determine benefit obligation at end of year [Abstract]
Discount rate	[1]	4.40%	3.70%
Health care cost trend rate [Abstract]
Initial rate		0.00%	0.00%
Ultimate rate		0.00%	0.00%
Pension Plan [Member] | Higman [Member]
Weighted-average assumption used to determine benefit obligation at end of year [Abstract]
Discount rate		4.40%		4.02%	4.13%
SERP [Member]
Weighted-average assumption used to determine benefit obligation at end of year [Abstract]
Discount rate	[1]	4.40%	3.70%
Rate of compensation increase		0.00%	0.00%
Health care cost trend rate [Abstract]
Initial rate		0.00%	0.00%
Ultimate rate		0.00%	0.00%
Other Postretirement Benefits [Member]
Weighted-average assumption used to determine benefit obligation at end of year [Abstract]
Discount rate	[1]	4.40%	3.70%
Rate of compensation increase		0.00%	0.00%
Health care cost trend rate [Abstract]
Initial rate		7.00%	7.00%
Ultimate rate		5.00%	5.00%
Years to ultimate		2,025	2,022
[1]	The discount rate for the Higman pension plan in 2018 was changed from 4.13% as of February 14, 2018 and 4.02% as of March 31, 2018 to 4.40% as of December 31, 2018.

Retirement Plans, Effect of One

Retirement Plans, Effect of One-Percentage-Point Change in Assumed Health Care Cost Trend Rate (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Pension Plan [Member]
Effect of one-percentage-point change in assumed health care cost trend rate on postretirement obligation[Abstract]
Effect of one-percentage-point change in assumed health care cost trend rate on postretirement obligation, Increase	$ 0	$ 0
Effect of one-percentage-point change in assumed health care cost trend rate on postretirement obligation, Decrease	0	0
SERP [Member]
Effect of one-percentage-point change in assumed health care cost trend rate on postretirement obligation[Abstract]
Effect of one-percentage-point change in assumed health care cost trend rate on postretirement obligation, Increase	0	0
Effect of one-percentage-point change in assumed health care cost trend rate on postretirement obligation, Decrease	0	0
Other Postretirement Benefits [Member]
Effect of one-percentage-point change in assumed health care cost trend rate on postretirement obligation[Abstract]
Effect of one-percentage-point change in assumed health care cost trend rate on postretirement obligation, Increase	75	75
Effect of one-percentage-point change in assumed health care cost trend rate on postretirement obligation, Decrease	(65)	(65)
Effect of one-percentage-point change in assumed health care cost trend rate on aggregate service and interest cost, Increase	3	3	$ 4
Effect of one-percentage-point change in assumed health care cost trend rate on aggregate service and interest cost, Decrease	$ (2)	$ (3)	$ (3)

Retirement Plans, Summary of Ch

Retirement Plans, Summary of Change in Plan Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Pension Plan [Member]
Change in plan assets [Roll Forward]
Fair value of plan assets at beginning of year	$ 294,995	$ 257,517
Actual return on plan assets	(18,214)	45,196
Employer contribution	8,102	0
Gross benefits paid	(11,749)	(7,718)
Acquisition	30,017	0
Fair value of plan assets at end of year	303,151	294,995
SERP [Member]
Change in plan assets [Roll Forward]
Fair value of plan assets at beginning of year	0	0
Actual return on plan assets	0	0
Employer contribution	145	145
Gross benefits paid	(145)	(145)
Acquisition	0	0
Fair value of plan assets at end of year	0	0
Other Postretirement Benefits [Member]
Change in plan assets [Roll Forward]
Fair value of plan assets at beginning of year	0	0
Actual return on plan assets	0	0
Employer contribution	103	75
Gross benefits paid	(103)	(75)
Acquisition	0	0
Fair value of plan assets at end of year	$ 0	$ 0

Retirement Plans, Summary of Fu

Retirement Plans, Summary of Funded Status at End of Year (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Pension Plan [Member]
Funded status at end of year [Abstract]
Fair value of plan assets	$ 303,151	$ 294,995	$ 257,517
Benefit obligations	(381,483)	(354,994)	(337,176)
Funded status and amount recognized at end of year	(78,332)	(59,999)
SERP [Member]
Funded status at end of year [Abstract]
Fair value of plan assets	0	0	0
Benefit obligations	(1,246)	(1,412)	(1,457)
Funded status and amount recognized at end of year	(1,246)	(1,412)
Other Postretirement Benefits [Member]
Funded status at end of year [Abstract]
Fair value of plan assets	0	0	0
Benefit obligations	(743)	(679)	$ (675)
Funded status and amount recognized at end of year	$ (743)	$ (679)

Retirement Plans, Amounts Recog

Retirement Plans, Amounts Recognized in Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Pension Plan [Member]
Amounts recognized in the consolidated balance sheets [Abstract]
Noncurrent asset	$ 0	$ 0
Current liability	0	0
Long-term liability	(78,332)	(59,999)
SERP [Member]
Amounts recognized in the consolidated balance sheets [Abstract]
Noncurrent asset	0	0
Current liability	(158)	(159)
Long-term liability	(1,087)	(1,253)
Other Postretirement Benefits [Member]
Amounts recognized in the consolidated balance sheets [Abstract]
Noncurrent asset	0	0
Current liability	(65)	(54)
Long-term liability	$ (678)	$ (625)

Retirement Plans, Amounts Rec_2

Retirement Plans, Amounts Recognized in Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Pension Plan [Member]
Amounts recognized in accumulated other comprehensive income [Abstract]
Net actuarial loss (gain)	$ 47,101	$ 57,387
Prior service cost (credit)	0	0
Accumulated other compensation income	47,101	57,387
SERP [Member]
Amounts recognized in accumulated other comprehensive income [Abstract]
Net actuarial loss (gain)	415	508
Prior service cost (credit)	0	0
Accumulated other compensation income	415	508
Other Postretirement Benefits [Member]
Amounts recognized in accumulated other comprehensive income [Abstract]
Net actuarial loss (gain)	(4,313)	(5,053)
Prior service cost (credit)	0	0
Accumulated other compensation income	$ (4,313)	$ (5,053)

Retirement Plans, Projected Ben

Retirement Plans, Projected Benefit Obligation in Excess of Plan Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Pension Plan [Member]
Projected benefit obligation in excess of plan assets [Abstract]
Projected benefit obligation at end of year	$ 381,483	$ 354,994
Fair value of plan assets at end of year	303,151	294,995
SERP [Member]
Projected benefit obligation in excess of plan assets [Abstract]
Projected benefit obligation at end of year	1,246	1,412
Fair value of plan assets at end of year	$ 0	$ 0

Retirement Plans, Accumulated B

Retirement Plans, Accumulated Benefit Obligation in Excess of Plan Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Pension Plan [Member]
Accumulated benefit obligation in excess of plan assets [Abstract]
Projected benefit obligation at end of year	$ 381,483	$ 354,994
Accumulated benefit obligation at end of year	356,797	324,904
Fair value of plan assets at end of year	303,151	294,995
SERP [Member]
Accumulated benefit obligation in excess of plan assets [Abstract]
Projected benefit obligation at end of year	1,246	1,412
Accumulated benefit obligation at end of year	1,246	1,412
Fair value of plan assets at end of year	$ 0	$ 0

Retirement Plans, Expected Empl

Retirement Plans, Expected Employer Contribution and Benefit Payments (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Pension Plan [Member]
Expected employer contributions [Abstract]
First year	$ 2,395	$ 0
Expected benefit payments (gross) [Abstract]
Year one	12,209	9,483
Year two	13,108	10,131
Year three	13,959	10,818
Year four	14,959	11,608
Year five	16,052	12,377
Next five years	96,547	75,717
SERP [Member]
Expected employer contributions [Abstract]
First year	162	162
Expected benefit payments (gross) [Abstract]
Year one	162	162
Year two	159	159
Year three	155	156
Year four	130	152
Year five	104	149
Next five years	447	462
Other Postretirement Benefits [Member]
Expected employer contributions [Abstract]
First year	66	48
Expected benefit payments (gross) [Abstract]
Year one	66	55
Year two	68	56
Year three	69	58
Year four	57	58
Year five	56	46
Next five years	$ 261	$ 214

Retirement Plans, Summary of Ex

Retirement Plans, Summary of Expected Federal Subsidy (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Pension Plan [Member]
Expected federal subsidy [Abstract]
Year one	$ 0	$ 0
Year two	0	0
Year three	0	0
Year four	0	0
Year five	0	0
Next five years	0	0
SERP [Member]
Expected federal subsidy [Abstract]
Year one	0	0
Year two	0	0
Year three	0	0
Year four	0	0
Year five	0	0
Next five years	0	0
Other Postretirement Benefits [Member]
Expected federal subsidy [Abstract]
Year one	0	(7)
Year two	0	(6)
Year three	0	(6)
Year four	0	(6)
Year five	0	(7)
Next five years	$ 0	$ (30)

Retirement Plans, Components of

Retirement Plans, Components of Net Periodic Benefit Cost, Pension Benefits (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Other changes in plan assets and benefit obligations recognized in other comprehensive income [Abstract]
Recognition of actuarial loss	[1]	$ (7,322)	$ (25,776)	$ 15,013
Recognition of prior service credit (cost)	[1]	(2,317)	(3,760)	(4,763)
Pension Plan [Member]
Components of net periodic benefit cost [Abstract]
Service cost		7,622	10,677	13,402
Interest cost		15,499	13,729	14,123
Expected return on plan assets		(22,406)	(18,195)	(16,805)
Actuarial loss (gain)		2,890	4,400	5,484
Prior service credit		0	0	0
Net periodic benefit cost		3,605	10,611	16,204
Other changes in plan assets and benefit obligations recognized in other comprehensive income [Abstract]
Current year actuarial loss (gain)		(7,396)	7,562	15,203
Recognition of actuarial loss		(2,890)	(37,833)	(5,484)
Recognition of prior service credit (cost)		0	0	0
Total recognized in other comprehensive income		(10,286)	(30,271)	9,719
Total recognized in net periodic benefit cost and other comprehensive income		(6,681)	(19,660)	25,923
SERP [Member]
Components of net periodic benefit cost [Abstract]
Service cost		0	0	0
Interest cost		49	58	65
Expected return on plan assets		0	0	0
Actuarial loss (gain)		23	28	26
Prior service credit		0	0	0
Net periodic benefit cost		72	86	91
Other changes in plan assets and benefit obligations recognized in other comprehensive income [Abstract]
Current year actuarial loss (gain)		(70)	42	12
Recognition of actuarial loss		(23)	(28)	(26)
Recognition of prior service credit (cost)		0	0	0
Total recognized in other comprehensive income		(93)	14	(14)
Total recognized in net periodic benefit cost and other comprehensive income		$ (21)	$ 100	$ 77
[1]	Actuarial gains (losses) are amortized into other income (expense). (See Note 11 - Retirement Plans)

Retirement Plans, Weighted Aver

Retirement Plans, Weighted Average Assumptions Used to Determine Net Periodic Benefit Cost, Pension Benefits (Details)		2 Months Ended		3 Months Ended	9 Months Ended		12 Months Ended
		Mar. 31, 2018	Feb. 14, 2018	Apr. 11, 2017	Sep. 30, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Pension Benefits [Member]
Weighted average assumptions used to determine net periodic benefit cost [Abstract]
Discount rate	[1]			4.20%		4.00%	3.70%		4.50%
Expected long-term rate of return on plan assets							7.00%	7.00%	7.50%
Pension Benefits [Member] | Higman [Member]
Weighted average assumptions used to determine net periodic benefit cost [Abstract]
Discount rate	[1]	4.02%	4.13%		4.40%
SERP [Member]
Weighted average assumptions used to determine net periodic benefit cost [Abstract]
Discount rate	[1]						3.70%	4.20%	4.50%
Expected long-term rate of return on plan assets							0.00%	0.00%	0.00%
Rate of compensation increase							0.00%	0.00%	0.00%
[1]	The 2018 discount rate for benefit cost for the Higman pension plan was changed from 4.13% as of February 14, 2018 and 4.02% as of March 31, 2018 to 4.40% as of December 31, 2018. In 2017, benefit cost for the pension plan was determined using a discount rate of 4.2% for the period beginning January 1, 2017 and ending April 11, 2017 and 4.0% for the period beginning April 12, 2017 and ending December 31, 2017.

Retirement Plans, Estimated Amo

Retirement Plans, Estimated Amounts That Will be Amortized from AOCI Into Net Periodic Benefit Cost, Pension Benefits (Details) $ in Thousands	Dec. 31, 2018USD ($)
Pension Plan [Member]
Estimated Amounts that will be Amortized from Accumulated Other Comprehensive Income into Net Periodic Benefit Cost [Abstract]
Actuarial gain (loss)	$ 2,713
Prior service cost (credit)	0
Estimated amounts to be amortized	2,713
SERP [Member]
Estimated Amounts that will be Amortized from Accumulated Other Comprehensive Income into Net Periodic Benefit Cost [Abstract]
Actuarial gain (loss)	28
Prior service cost (credit)	0
Estimated amounts to be amortized	$ 28

Retirement Plans, Components _2

Retirement Plans, Components of Net Periodic Benefit Cost, Other Postretirement Benefits (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Other changes in plan assets and benefit obligations recognized in other comprehensive income [Abstract]
Recognition of actuarial gain	[1]	$ (7,322)	$ (25,776)	$ 15,013
Recognition of prior service credit (cost)	[1]	(2,317)	(3,760)	(4,763)
Other Postretirement Benefits [Member]
Components of net periodic benefit cost [Abstract]
Service cost		0	0	0
Interest cost		24	27	29
Actuarial gain		(596)	(668)	(747)
Prior service cost		0	0	0
Net periodic benefit cost		(572)	(641)	(718)
Other changes in plan assets and benefit obligations recognized in other comprehensive income [Abstract]
Current year actuarial loss (gain)		144	52	(198)
Recognition of actuarial gain		596	668	747
Recognition of prior service credit (cost)		0	0	0
Adjustment for actual Medicare Part D reimbursement		0	0	(3)
Total recognized in other comprehensive income		740	720	546
Total recognized in net periodic benefit cost and other comprehensive income		$ 168	$ 79	$ (172)
[1]	Actuarial gains (losses) are amortized into other income (expense). (See Note 11 - Retirement Plans)

Retirement Plans, Weighted Av_2

Retirement Plans, Weighted Average Assumptions Used to Determine Net Periodic Benefit Cost, Other Postretirement Benefits (Details) - Other Postretirement Benefits [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Weighted average assumptions used to determine net periodic benefit cost [Abstract]
Discount rate	3.70%	4.20%	4.50%
Health care cost trend rate [Abstract]
Initial rate	7.00%	7.00%	6.50%
Ultimate rate	5.00%	5.00%	5.00%
Years to ultimate	2,022	2,021	2,019
Effect of one-percentage-point change in assumed health care cost trend rate on postretirement obligation[Abstract]
Effect of one-percentage-point change in assumed health care cost trend rate on aggregate service and interest cost, Increase	$ 3	$ 3	$ 4
Effect of one-percentage-point change in assumed health care cost trend rate on aggregate service and interest cost, Decrease	$ (2)	$ (3)	$ (3)

Retirement Plans, Estimated A_2

Retirement Plans, Estimated Amounts That Will be Amortized from AOCI Into Net Periodic Benefit Cost, Other Postretirement Benefits (Details) - Other Postretirement Benefits [Member] $ in Thousands	Dec. 31, 2018USD ($)
Estimated Amounts that will be Amortized from Accumulated Other Comprehensive Income into Net Periodic Benefit Cost [Abstract]
Actuarial gain	$ (540)
Prior service cost	0
Estimated amounts to be amortized	$ (540)

Retirement Plans, Multiemployer

Retirement Plans, Multiemployer Pension Plan and Defined Contribution Plans (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Retirement Plans [Abstract]
Aggregate contributions to the plans	$ 22,392	$ 17,247	$ 18,213
Seafarers Pension Trust [Member]
Retirement Plans [Abstract]
Pension contributions	$ 671	896
Contribution percentage to defined contribution plan	100.00%
Maximum contribution limit	5.00%
CPF [Member]
Retirement Plans [Abstract]
Pension contributions	$ 736	$ 238
Contribution percentage to defined contribution plan		94.00%

Other Comprehensive Income (Det

Other Comprehensive Income (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Pension and postretirement benefits [Abstract]
Amortization of net actuarial loss, Gross Amount	[1]	$ 2,317	$ 3,760	$ 4,763
Amortization of net actuarial loss, Income Tax (Provision) Benefit	[1]	(585)	(1,417)	(1,825)
Amortization of net actuarial loss, Net Amount	[1]	1,732	2,343	2,938
Actuarial gains (losses), Gross Amount	[1]	7,322	25,776	(15,013)
Actuarial gains (losses), Income Tax (Provision) Benefit	[1]	(1,416)	(9,371)	5,754
Actuarial gains (losses), Net Amount	[1]	5,906	16,405	(9,259)
Foreign currency translation adjustments, Gross Amount		(819)	(146)	0
Foreign currency translation adjustments, Income Tax (Provision) Benefit		0	0	0
Foreign currency translation adjustments, Net Amount		(819)	(146)	0
Total other comprehensive income, Gross Amount		8,820	29,390	(10,250)
Total other comprehensive income, Income Tax (Provision) Benefit		(9,926)	(10,788)	3,929
Total other comprehensive income (loss), net of taxes		(1,106)	18,602	(6,321)
ASU 2018-02 [Member]
Pension and postretirement benefits [Abstract]
Adoption of ASU 2018-02 - reclassification to retained earnings, Gross Amount		0	0	0
Adoption of ASU 2018-02 - reclassification to retained earnings, Income Tax (Provision) Benefit		(7,925)	0	0
Adoption of ASU 2018-02 - reclassification to retained earnings, Net Amount		$ (7,925)	$ 0	$ 0
[1]	Actuarial gains (losses) are amortized into other income (expense). (See Note 11 - Retirement Plans)

Earnings Per Share (Details)

Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Earnings Per Share [Abstract]
Net earnings attributable to Kirby	$ (24,437)	$ 41,816	$ 28,602	$ 32,471	$ 231,319	$ 28,607	$ 25,778	$ 27,483	$ 78,452	$ 313,187	$ 141,406
Undistributed earnings allocated to restricted shares									(324)	(2,213)	(999)
Income available to Kirby common stockholders - basic									78,128	310,974	140,407
Undistributed earnings allocated to restricted shares									324	2,213	999
Undistributed earnings reallocated to restricted shares									(323)	(2,211)	(997)
Income available to Kirby common stockholders - diluted									$ 78,129	$ 310,976	$ 140,409
Shares outstanding [Abstract]
Weighted average common stock issued and outstanding (in shares)									59,804	55,702	53,834
Weighted average unvested restricted stock (in shares)									(247)	(394)	(380)
Weighted average common stock outstanding - basic (in shares)									59,557	55,308	53,454
Dilutive effect of stock options and restricted stock units (in shares)									132	53	58
Weighted average common stock outstanding - diluted (in shares)									59,689	55,361	53,512
Net earnings per share attributable to Kirby common stockholders [Abstract]
Basic (in dollars per share)	$ (0.41)	$ 0.70	$ 0.48	$ 0.54	$ 3.88	$ 0.52	$ 0.48	$ 0.51	$ 1.31	$ 5.62	$ 2.63
Diluted (in dollars per share)	$ (0.41)	$ 0.70	$ 0.48	$ 0.54	$ 3.87	$ 0.52	$ 0.48	$ 0.51	$ 1.31	$ 5.62	$ 2.62
Antidilutive securities excluded from computation of earnings per share (in shares)									384	472	240

Quarterly Results (Unaudited)_2

Quarterly Results (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Quarterly Results (Unaudited) [Abstract]
Revenues	$ 721,493	$ 704,845	$ 802,671	$ 741,688	$ 708,111	$ 541,274	$ 473,328	$ 491,705
Costs and expenses	740,344	636,906	747,260	692,866	756,423	488,186	425,937	445,760
Gain (loss) on disposition of assets	(390)	18	442	1,898	(4,288)	(159)	(139)	99	$ 1,968	$ (4,487)	$ (127)
Operating income	(19,241)	67,957	55,853	50,720	(52,600)	52,929	47,252	46,044	155,289	93,625	247,370
Nonoperating expense	1,140	1,454	1,541	1,591	902	320	228	(589)
Interest expense	(12,191)	(12,345)	(12,540)	(9,780)	(7,162)	(5,388)	(4,465)	(4,457)	(46,856)	(21,472)	(17,690)
Earnings before taxes on income	(30,292)	57,066	44,854	42,531	(58,860)	47,861	43,015	40,998	114,159	73,014	227,746
Benefit (provision) for taxes on income	5,961	(15,116)	(16,061)	(9,865)	290,357	(19,072)	(17,043)	(13,353)	(35,081)	240,889	(84,942)
Net earnings	(24,331)	41,950	28,793	32,666	231,497	28,789	25,972	27,645	79,078	313,903	142,804
Less: Net earnings attributable to noncontrolling interests	(106)	(134)	(191)	(195)	(178)	(182)	(194)	(162)	(626)	(716)	(1,398)
Net earnings attributable to Kirby	$ (24,437)	$ 41,816	$ 28,602	$ 32,471	$ 231,319	$ 28,607	$ 25,778	$ 27,483	$ 78,452	$ 313,187	$ 141,406
Net earnings per share attributable to Kirby common stockholders [Abstract]
Basic (in dollars per share)	$ (0.41)	$ 0.70	$ 0.48	$ 0.54	$ 3.88	$ 0.52	$ 0.48	$ 0.51	$ 1.31	$ 5.62	$ 2.63
Diluted (in dollars per share)	$ (0.41)	$ 0.70	$ 0.48	$ 0.54	$ 3.87	$ 0.52	$ 0.48	$ 0.51	$ 1.31	$ 5.62	$ 2.62

Contingencies and Commitments (

Contingencies and Commitments (Details)	12 Months Ended
	Dec. 31, 2018PotentiallyResponsiblePartySpillBargeSlipLawsuitPlaintiff	Mar. 22, 2014TankBargeVessel
Collision with M/S Summer Wind [Member]
Loss Contingency [Abstract]
Number of vessels involved in collision | Vessel		2
Number of vessels damaged in collision resulting in fuel oil discharge | TankBarge		1
Number of actions filed against the Company | Lawsuit	2
Number of crewmembers alleging damages | Plaintiff	2
Portland Harbor Superfund Site [Member]
Site Contingency [Line Items]
Number of other companies also named as Potentially Responsible Parties ("PRPs") | PotentiallyResponsibleParty	250
Number of spills | Spill	4
SBA Shipyard Site [Member]
Site Contingency [Line Items]
Number of barge slips | BargeSlip	3

Contingencies and Commitments,

Contingencies and Commitments, Certain Significant Risks and Uncertainties (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2018USD ($)CustomersDistributor	Dec. 31, 2017Customers	Dec. 31, 2016Customers
Guaranties [Abstract]
Issued guaranties	$ 20,133
Maximum [Member]
Guaranties [Abstract]
Guarantor obligations, expiration period	2 years
Performance Bonds [Member]
Guaranties [Abstract]
Issued guaranties	$ 11,954
Marine Transportation [Member]
Certain Significant Risks and Uncertainties [Abstract]
Percentage of inland revenue	65.00%
Marine Transportation [Member] | Minimum [Member]
Certain Significant Risks and Uncertainties [Abstract]
Range of renewal options under term contracts	1 year
Marine Transportation [Member] | Maximum [Member]
Certain Significant Risks and Uncertainties [Abstract]
Range of renewal options under term contracts	3 years
Marine Transportation [Member] | Customers [Member]
Certain Significant Risks and Uncertainties [Abstract]
Percentage of costal revenue	80.00%
Customer relationship period	40 years
Number of single customers accounting more than 10% of segment revenue | Customers	0	0	0
Distribution and Services [Member]
Certain Significant Risks and Uncertainties [Abstract]
Number of off-highway top distributors | Distributor	5
Services segment's relationship term	53 years
Distribution and Services [Member] | Customers [Member]
Certain Significant Risks and Uncertainties [Abstract]
Number of single customers accounting more than 10% of segment revenue | Customers	0	0	0
Letters Of Credit [Member]
Guaranties [Abstract]
Issued guaranties	$ 8,179

Segment Data (Details)

Segment Data (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018USD ($)	Sep. 30, 2018USD ($)	Jun. 30, 2018USD ($)	Mar. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Sep. 30, 2017USD ($)	Jun. 30, 2017USD ($)	Mar. 31, 2017USD ($)	Dec. 31, 2018USD ($)Segment	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Segment Data [Abstract]
Number of reportable segments | Segment									2
Revenues [Abstract]
Revenues									$ 2,970,697	$ 2,214,418	$ 1,770,673
Segment profit (loss)	$ (30,292)	$ 57,066	$ 44,854	$ 42,531	$ (58,860)	$ 47,861	$ 43,015	$ 40,998	114,159	73,014	227,746
Total assets	5,871,594				5,127,427				5,871,594	5,127,427	4,289,895
Depreciation and amortization									224,972	202,881	200,917
Capital expenditures									301,861	177,222	231,066
Other segment disclosures [Abstract]
Interest expense	(12,191)	(12,345)	(12,540)	(9,780)	(7,162)	(5,388)	(4,465)	(4,457)	(46,856)	(21,472)	(17,690)
Impairment of long-lived assets	(82,705)				(105,712)				(82,705)	(105,712)	0
Impairment of goodwill									(2,702)	0	0
Lease Cancellation Costs									(2,403)	0	0
Gain (loss) on disposition of assets	(390)	18	442	1,898	(4,288)	(159)	(139)	99	1,968	(4,487)	(127)
Nonoperating expense	1,140	1,454	1,541	1,591	902	320	228	(589)
Earnings before taxes on income	(30,292)	$ 57,066	$ 44,854	$ 42,531	(58,860)	$ 47,861	$ 43,015	$ 40,998	114,159	73,014	227,746
Details of "Other" total assets [Abstract]
Investment in affiliates	2,495				1,890				2,495	1,890
Marine Transportation [Member]
Revenues [Abstract]
Revenues									1,483,143	1,324,106	1,471,893
Distribution and Services [Member]
Revenues [Abstract]
Revenues									1,487,554	890,312	298,780
Other [Member]
Revenues [Abstract]
Segment profit (loss)									(162,562)	(149,012)	(34,775)
Total assets	72,664				75,243				72,664	75,243	52,676
Depreciation and amortization									3,316	3,596	3,793
Capital expenditures									6,166	6,715	7,728
Other segment disclosures [Abstract]
General corporate expenses									(35,590)	(18,202)	(15,024)
Interest expense									(46,856)	(21,472)	(17,690)
Impairment of long-lived assets									(82,705)	(105,712)	0
Impairment of goodwill									(2,702)	0	0
Lease Cancellation Costs									(2,403)	0	0
Gain (loss) on disposition of assets									1,968	(4,487)	(127)
Nonoperating expense									5,726	861	(1,934)
Earnings before taxes on income									(162,562)	(149,012)	(34,775)
Details of "Other" total assets [Abstract]
General corporate assets	70,169				73,353				70,169	73,353	50,054
Investment in affiliates	2,495				1,890				2,495	1,890	2,622
Total other assets	72,664				75,243				72,664	75,243	52,676
Reportable Segments [Member] | Marine Transportation [Member]
Revenues [Abstract]
Revenues									1,483,143	1,324,106	1,471,893
Segment profit (loss)									147,416	135,547	259,453
Total assets	4,145,294				3,485,099				4,145,294	3,485,099	3,613,951
Depreciation and amortization									182,307	178,898	184,291
Capital expenditures									284,953	165,421	217,423
Other segment disclosures [Abstract]
Earnings before taxes on income									147,416	135,547	259,453
Reportable Segments [Member] | Distribution and Services [Member]
Revenues [Abstract]
Revenues									1,487,554	890,312	298,780
Segment profit (loss)									129,305	86,479	3,068
Total assets	$ 1,653,636				$ 1,567,085				1,653,636	1,567,085	623,268
Depreciation and amortization									39,349	20,387	12,833
Capital expenditures									10,742	5,086	5,915
Other segment disclosures [Abstract]
Earnings before taxes on income									129,305	86,479	3,068
Intersegment Eliminations [Member]
Revenues [Abstract]
Revenues									29,363	20,717	24,672
Segment profit (loss)									29,363	2,072	2,467
Other segment disclosures [Abstract]
Earnings before taxes on income									$ 29,363	$ 2,072	$ 2,467

Related Party Transactions (Det

Related Party Transactions (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Hollywood Camp [Member]
Related Party [Abstract]
Ownership percentage	50.00%
Related party expenses	$ 4,523	$ 3,634	$ 3,143
Strasburger & Price, LLP [Member]
Related Party [Abstract]
Legal services	$ 2,019	830	779
Bolivar [Member]
Related Party [Abstract]
Ownership percentage	50.00%
Related party expenses	$ 461	$ 581	$ 1,314

Subsequent Events (Details)

Subsequent Events (Details) $ in Millions	Jan. 29, 2019USD ($)bblTankBargeTowboatTugboat	Nov. 30, 2018Towboat
Inland Towboats [Member]
Acquisitions [Abstract]
Number of maritime vessels acquired | Towboat		1
Subsequent Event [Member] | Cenac Marine Services, LLC [Member]
Acquisitions [Abstract]
Cash paid for acquisition | $	$ 244
Subsequent Event [Member] | Cenac Marine Services, LLC [Member] | Inland Barrel Tank Barges [Member]
Acquisitions [Abstract]
Number of maritime vessels acquired | TankBarge	63
Tank barge barrel capacity (in barrels) | bbl	30,000
Aggregate tank barge barrel capacity (in barrels) | bbl	1,900,000
Subsequent Event [Member] | Cenac Marine Services, LLC [Member] | Inland Towboats [Member]
Acquisitions [Abstract]
Number of maritime vessels acquired | Towboat	34
Subsequent Event [Member] | Cenac Marine Services, LLC [Member] | Offshore Tugboats [Member]
Acquisitions [Abstract]
Number of maritime vessels acquired | Tugboat	2