XML 62 R34.htm IDEA: XBRL DOCUMENT
v3.19.3.a.u2

EMPLOYEE BENEFIT PLANS (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2019
EMPLOYEE BENEFIT PLANS |
Schedule of changes in benefit obligations and plan assets and disclosure of funded status and accumulated benefit obligation of nonunion defined benefit plans | The following table discloses the changes in benefit obligations and plan assets of the Company’s nonunion defined benefit plans for years ended December 31, the measurement date of the plans: ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Nonunion Defined | ​ | Supplemental | ​ | Postretirement |
​ | ​ | Benefit Pension Plan | ​ | Benefit Plan | ​ | Health Benefit Plan |
​ |  | 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018 |
​ | ​ | (in thousands) |
Change in benefit obligations | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Benefit obligations at December 31, 2018 | ​ | $ | 33,373 | ​ | $ | 137,417 | ​ | $ | 3,948 | ​ | $ | 3,897 | ​ | $ | 29,488 | ​ | $ | 24,097 | ​
Service cost | ​ |  | — | ​ |  | — | ​ |  | — | ​ |  | — | ​ |  | 320 | ​ |  | 366 | ​
Interest cost | ​ |  | 624 | ​ |  | 4,269 | ​ |  | 39 | ​ |  | 108 | ​ |  | 1,212 | ​ |  | 837 | ​
Actuarial (gain) loss(1) | ​ |  | 300 | ​ |  | (3,685) | ​ |  | 186 | ​ |  | (57) | ​ |  | (9,542) | ​ |  | 4,957 | ​
Benefits paid | ​ |  | (34,297) | ​ |  | (105,522) | ​ |  | (937) | ​ |  | — | ​ |  | (848) | ​ |  | (769) | ​
Settlement loss | ​ |  | — | ​ |  | 894 | ​ |  | — | ​ |  | — | ​ |  | — | ​ |  | — | ​
Benefit obligations at December 31, 2019 | ​ |  | — | ​ |  | 33,373 | ​ |  | 3,236 | ​ |  | 3,948 | ​ |  | 20,630 | ​ |  | 29,488 | ​
Change in plan assets | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Fair value of plan assets at December 31, 2018 | ​ |  | 26,646 | ​ |  | 124,831 | ​ |  | — | ​ |  | — | ​ |  | — | ​ |  | — | ​
Actual return on plan assets | ​ |  | (59) | ​ |  | 1,837 | ​ |  | — | ​ |  | — | ​ |  | — | ​ |  | — | ​
Employer contributions | ​ |  | 7,710 | ​ |  | 5,500 | ​ |  | 937 | ​ |  | — | ​ |  | 848 | ​ |  | 769 | ​
Benefits paid | ​ |  | (34,297) | ​ |  | (105,522) | ​ |  | (937) | ​ |  | — | ​ |  | (848) | ​ |  | (769) | ​
Fair value of plan assets at December 31, 2019 | ​ |  | — | ​ |  | 26,646 | ​ |  | — | ​ |  | — | ​ |  | — | ​ |  | — | ​
Funded status at period end | ​ | $ | — | ​ | $ | (6,727) | ​ | $ | (3,236) | ​ | $ | (3,948) | ​ | $ | (20,630) | ​ | $ | (29,488) | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Accumulated benefit obligation | ​ | $ | — | ​ | $ | 33,373 | ​ | $ | 3,236 | ​ | $ | 3,948 | ​ | $ | 20,630 | ​ | $ | 29,488 | ​
(1) | The actuarial gain on the nonunion defined benefit pension plan for 2018 was primarily due to an increase in the discount rate used to remeasure the plan obligation at December 31, 2018 versus December 31, 2017. The actuarial gain on the postretirement health benefit plan for 2019 is primarily related to the impact of a lower cost prescription drug plan effective January 1, 2020, versus the actuarial loss for 2018 which was primarily related to changes in the medical trend rate assumption used to measure the plan obligation at the measurement date.
Schedule of amounts recognized in the consolidated balance sheets related to nonunion defined benefit plans | Amounts recognized in the consolidated balance sheets at December 31 consisted of the following: ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Nonunion Defined | ​ | Supplemental | ​ | Postretirement |
​ | ​ | Benefit Pension Plan | ​ | Benefit Plan | ​ | Health Benefit Plan |
​ |  | 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018 |
​ | ​ | (in thousands) |
Current portion of pension and postretirement liabilities | ​ | $ | — | ​ | $ | (6,727) | ​ | $ | (2,886) | ​ | $ | (937) | ​ | $ | (686) | ​ | $ | (995) | ​
Pension and postretirement liabilities, less current portion | ​ |  | — | ​ |  | — | ​ |  | (350) | ​ |  | (3,011) | ​ |  | (19,944) | ​ |  | (28,493) | ​
Liabilities recognized | ​ | $ | — | ​ | $ | (6,727) | ​ | $ | (3,236) | ​ | $ | (3,948) | ​ | $ | (20,630) | ​ | $ | (29,488) | ​
​
Summary of the components of net periodic benefit cost | The following is a summary of the components of net periodic benefit cost for the Company’s nonunion benefit plans for the years ended December 31: ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Nonunion Defined | ​ | Supplemental | ​ | Postretirement | ​
​ | ​ | Benefit Pension Plan | ​ | Benefit Plan | ​ | Health Benefit Plan | ​
​ |  | 2019 |  | 2018 |  | 2017 |  | 2019 |  | 2018 |  | 2017 |  | 2019 |  | 2018 |  | 2017 |
​ | ​ | (in thousands) | ​ |  | ​ | ​
Service cost | ​ | $ | — | ​ | $ | — | ​ | $ | — | ​ | $ | — | ​ | $ | — | ​ | $ | — | ​ | $ | 320 | ​ | $ | 366 | ​ | $ | 489 | ​
Interest cost | ​ |  | 624 | ​ |  | 4,269 | ​ |  | 4,514 | ​ |  | 39 | ​ |  | 108 | ​ |  | 102 | ​ |  | 1,212 | ​ |  | 837 | ​ |  | 1,060 | ​
Expected return on plan assets | ​ |  | (31) | ​ |  | (1,582) | ​ |  | (5,712) | ​ |  | — | ​ |  | — | ​ |  | — | ​ |  | — | ​ |  | — | ​ |  | — | ​
Amortization of prior service credit | ​ |  | — | ​ |  | — | ​ |  | — | ​ |  | — | ​ |  | — | ​ |  | — | ​ |  | (33) | ​ |  | (93) | ​ |  | (190) | ​
Pension settlement expense(1) | ​ |  | 4,164 | ​ |  | 12,925 | ​ |  | 4,156 | ​ |  | 370 | ​ |  | — | ​ |  | — | ​ |  | — | ​ |  | — | ​ |  | — | ​
Amortization of net actuarial loss(2) | ​ |  | 260 | ​ |  | 2,583 | ​ |  | 3,132 | ​ |  | 95 | ​ |  | 81 | ​ |  | 82 | ​ |  | 898 | ​ |  | 304 | ​ |  | 694 | ​
Net periodic benefit cost | ​ | $ | 5,017 | ​ | $ | 18,195 | ​ | $ | 6,090 | ​ | $ | 504 | ​ | $ | 189 | ​ | $ | 184 | ​ | $ | 2,397 | ​ | $ | 1,414 | ​ | $ | 2,053 | ​
(1) | For 2019, the presentation of pension settlement expense excludes a $4.0 million noncash pension termination expense which is further described within this Note.
(2) | The Company amortizes actuarial losses over the average remaining active service period of the plan participants and does not use a corridor approach.
​
Summary of pension settlement distributions and settlement expense | The following is a summary of the pension settlement distributions and pension settlement expense for the years ended December 31: ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Nonunion Defined | ​ | Supplemental |
​ | ​ | Benefit Pension Plan | ​ | Benefit Plan |
​ |  | 2019(1) |  | 2018(2) |  | 2017(3) |  | 2019(4) |  | 2018 |  | 2017(5) |
​ | ​ | (in thousands, except per share data) |
Pension settlement distributions | ​ | $ | 33,938 | ​ | $ | 105,279 | ​ | $ | 26,261 | ​ | $ | 937 | ​ | $ | — | ​ | $ | 989 | ​
Pension settlement expense, pre-tax(6) | ​ | $ | 4,164 | ​ | $ | 12,925 | ​ | $ | 4,156 | ​ | $ | 370 | ​ | $ | — | ​ | $ | — | ​
Pension settlement expense per diluted share, net of taxes | ​ | $ | 0.12 | ​ | $ | 0.36 | ​ | $ | 0.10 | ​ | $ | 0.01 | ​ | $ | — | ​ | $ | — | ​
(1) | Pension settlement distributions for 2019 represent $18.4 million of lump-sum benefit distributions, including participant-elected distributions associated with the plan’s termination, a $14.0 million nonparticipating annuity contract purchase, and a $1.5 million transfer of benefit obligations to the PBGC.
(2) | Pension settlement distributions for 2018 represent lump-sum benefit distributions, including participant-elected distributions associated with the plan’s termination.
(3) | Pension settlement distributions for 2017 represent $18.7 million of lump-sum benefit distributions and a $7.6 million nonparticipating annuity contract purchase.
(4) | The 2019 SBP distribution excludes the portion of the benefit related to an officer retirement which is delayed for six months after retirement in accordance with IRC Section 409A. The pension settlement expense related to the delayed distribution is recognized in 2019.
(5) | The 2017 SBP distribution represents the portion of a benefit related to an officer retirement that occurred in 2016 which was delayed for six months after retirement in accordance with IRC Section 409A. The pension settlement expense related to this distribution was recognized in 2016.
(6) | For 2019, the presentation of pension settlement expense excludes a $4.0 million noncash pension termination expense which is further described within this Note.
​
Pre-tax amounts included in accumulated other comprehensive loss that have not yet been recognized in net periodic benefit cost | Included in accumulated other comprehensive loss at December 31 were the following pre-tax amounts that have not yet been recognized in net periodic benefit cost: ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Nonunion Defined | ​ | Supplemental | ​ | Postretirement |
​ | ​ | Benefit Pension Plan | ​ | Benefit Plan | ​ | Health Benefit Plan |
​ |  | 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018 |
​ | ​ | (in thousands) |
Unrecognized net actuarial (gain) loss | ​ | $ | — | ​ | $ | 4,034 | ​ | $ | 127 | ​ | $ | 405 | ​ | $ | (3,024) | ​ | $ | 7,416 | ​
Unrecognized prior service credit | ​ |  | — | ​ |  | — | ​ |  | — | ​ |  | — | ​ |  | (1) | ​ |  | (34) | ​
Total | ​ | $ | — | ​ | $ | 4,034 | ​ | $ | 127 | ​ | $ | 405 | ​ | $ | (3,025) | ​ | $ | 7,382 | ​
Weighted-average assumptions used to determine benefit obligations and net periodic benefit cost for nonunion defined benefit plans | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Nonunion Defined | ​ | Supplemental | ​ | Postretirement |
​ | ​ | Benefit Pension Plan | ​ | Benefit Plan | ​ | Health Benefit Plan |
​ |  | 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018 |
Discount rate | ​ | N/A | ​ | 3.9 | % | 2.4 | % | 3.6 | % | 3.1 | % | 4.2 | %
​ Weighted-average assumptions used to determine net periodic benefit cost for the Company’s nonunion benefit plans for the years ended December 31 were as follows: ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Nonunion Defined | ​ | Supplemental | ​ | Postretirement |
​ | ​ | Benefit Pension Plan | ​ | Benefit Plan | ​ | Health Benefit Plan |
​ |  | 2019(1) |  | 2018(2) |  | 2017(3) |  | 2019 |  | 2018 |  | 2017 |  | 2019 |  | 2018 |  | 2017 |
Discount rate | ​ | 3.9 | % | 3.1 | % | 3.4 | % | 3.6 | % | 2.8 | % | 2.7 | % | 4.2 | % | 3.5 | % | 4.0 | %
Expected return on plan assets | ​ | 1.4 | % | 1.4 | % | 6.5 | % | N/A |  | N/A |  | N/A |  | N/A |  | N/A |  | N/A | ​
(1) | The discount rate presented was used to determine the first quarter 2019 expense, and the short-term discount rate established upon quarterly settlements in 2019 of 3.8% and 3.7%, was used to calculate the expense for the second and third quarter of 2019, respectively. The expected return on plan assets presented was used to determine nonunion pension expense for first quarter 2019, and a 0.0% expected return on plan assets was used to determine nonunion pension expense for the second and third quarters of 2019, as further discussed in the following Nonunion Defined Benefit Pension Plan Assets section within this Note.
(2) | The discount rate presented was used to determine the first quarter 2018 credit, and the interim discount rate established upon each quarterly settlement in 2018 of 3.6%, 3.8%, and 3.6% was used to calculate the expense for the second, third, and fourth quarter of 2018, respectively.
(3) | The discount rate presented was used to determine the first quarter 2017 credit, and the interim discount rate established upon each quarterly settlement in 2017 of 3.4%, 3.2%, and 3.1% was used to calculate the expense/credit for the second, third, and fourth quarter of 2017, respectively. The expected return on plan assets presented was used to determine the nonunion pension credit for the first half of 2017, and a 2.5% expected return on plan assets was used to determine nonunion pension expense for the second half of 2017, as further discussed in the following Nonunion Defined Benefit Pension Plan Assets section within this Note.
Schedule of the assumed health care cost trend rates for the postretirement health benefit plan | The assumed health care cost trend rates for the Company’s postretirement health benefit plan at December 31 were as follows: ​
​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | ​
​ |  | 2019 |  | 2018 |
Health care cost trend rate assumed for next year(1) | ​ | 7.5 | % | 8.0 | %
Rate to which the cost trend rate is assumed to decline | ​ | 5.0 | % | 5.0 | %
Year that the rate reaches the cost trend assumed rate |  | 2026 |  | 2026 |
(1) | At each December 31 measurement date, health care cost rates for the following year are based on known premiums for the fully-insured postretirement health benefit plan. Therefore, the first year of assumed health care cost trend rates presented as of December 31, 2019 and 2018 are for 2021 and 2020, respectively.
Schedule of estimated future benefit payments for nonunion defined benefit plans | Estimated future benefit payments from the Company’s SBP and postretirement health benefit plans, which reflect expected future service as appropriate, as of December 31, 2019 are as follows: ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ |  | Supplemental |  | Postretirement |
​ | ​ | Benefit | ​ | Health |
​ | ​ | Plan | ​ | Benefit Plan |
​ | ​ | ​ | ​ | ​ | ​ | ​ |
2020 | ​ | $ | 2,886 | ​ | $ | 686 | ​
2021 | ​ | $ | — | ​ | $ | 735 | ​
2022 | ​ | $ | — | ​ | $ | 754 | ​
2023 | ​ | $ | — | ​ | $ | 849 | ​
2024 | ​ | $ | — | ​ | $ | 815 | ​
2025-2029 | ​ | $ | 424 | ​ | $ | 4,428 | ​
Fair value of the nonunion defined benefit pension plan assets, by major asset category and fair value hierarchy level | The fair value of the Company’s nonunion defined benefit pension plan assets at December 31, 2018, by major asset category and fair value hierarchy level (see Fair Value Measurements accounting policy in Note B), were as follows: ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | Fair Value Measurements Using | ​
​ | ​ | ​ | ​ | ​ | Quoted Prices |  | Significant |  | Significant | ​
​ | ​ | ​ | ​ | ​ | In Active | ​ | Observable | ​ | Unobservable | ​
​ | ​ | ​ | ​ | ​ | Markets | ​ | Inputs | ​ | Inputs | ​
​ |  | Total |  | (Level 1) |  | (Level 2) |  | (Level 3) |
​ | ​ | (in thousands) | ​
Cash and cash equivalents(1) | ​ | $ | 19,856 | ​ | $ | 19,856 | ​ | $ | — | ​ | $ | — | ​
Debt instruments(2) | ​ |  | 10 | ​ |  | — | ​ |  | 10 | ​ |  | — | ​
Floating rate loans(3) | ​ |  | 6,780 | ​ |  | 6,780 | ​ |  | — | ​ |  | — | ​
Fair value of plan assets at December 31, 2018 | ​ | $ | 26,646 | ​ | $ | 26,636 | ​ | $ | 10 | ​ | $ | — | ​
(1) | Consists primarily of money market mutual funds.
(2) | Includes a debt income security which was liquidated subsequent to December 31, 2018. The sale price of the security was used to determine the fair value at December 31, 2018.
(3) | Consists of a floating rate loan mutual fund.
​
Schedule of multiemployer pension funds and key participation information | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | Pension | ​ | FIP/RP | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ |
​ | ​ | ​ | ​ | Protection Act | ​ | Status | ​ | Contributions (d) | ​ | ​
​ | ​ | EIN/Pension | ​ | Zone Status (b) | ​ | Pending/ | ​ | (in thousands) | ​ | Surcharge
Legal Name of Plan |  | Plan Number (a) |  | 2019 |  | 2018 |  | Implemented (c) |  | 2019 |  | 2018 |  | 2017 |  | Imposed (e)
Central States, Southeast and Southwest Areas Pension Plan(1)(2) |  | 36-6044243 |  | Critical and Declining |  | Critical and Declining |  | Implemented(3) | ​ | $ | 75,803 | ​ | $ | 74,177 | ​ | $ | 78,230 |  | No
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Western Conference of Teamsters Pension Plan(2) |  | 91-6145047 |  | Green |  | Green |  | No | ​ |  | 24,860 | ​ |  | 25,268 | ​ |  | 26,320 |  | No
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Central Pennsylvania Teamsters Defined Benefit Plan(1)(2) |  | 23-6262789 |  | Green |  | Green |  | No | ​ |  | 13,907 | ​ |  | 13,393 | ​ |  | 13,391 |  | No
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
I. B. of T. Union Local No. 710 Pension Fund(5)(6) |  | 36-2377656 |  | Green(4) |  | Green(4) |  | No | ​ |  | 10,164 | ​ |  | 9,929 | ​ |  | 10,054 |  | No
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
New England Teamsters Pension Fund(7)(8) |  | 04-6372430 |  | Critical and Declining(9) |  | Critical and Declining(9) |  | Implemented(10) | ​ |  | 4,802 | ​ |  | 20,090 | ​ |  | 5,026 | ​ | No
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
All other plans in the aggregate | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ |  | 24,210 | ​ |  | 24,392 | ​ |  | 25,395 | ​ | ​
Total multiemployer pension contributions paid(11) | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | $ | 153,746 | ​ | $ | 167,249 | ​ | $ | 158,416 | ​ | ​
Table Heading Definitions ​
(a) | The “EIN/Pension Plan Number” column provides the Federal Employer Identification Number (EIN) and the three-digit plan number, if applicable.
(b) | Unless otherwise noted, the most recent PPA zone status available in 2019 and 2018 is for the plan’s year-end status at December 31, 2018 and 2017, respectively. The zone status is based on information received from the plan and was certified by the plan’s actuary. Green zone funds are those that are in neither endangered, critical, or critical and declining status and generally have a funded percentage of at least 80%.
(c) | The “FIP/RP Status Pending/Implemented” column indicates if a funding improvement plan (FIP) or a rehabilitation plan (RP), if applicable, is pending or has been implemented.
(d) | Amounts reflect contributions made in the respective year and differ from amounts expensed during the year.
(e) | The surcharge column indicates if a surcharge was paid by ABF Freight to the plan.
​
| (1) | ABF Freight System, Inc. was listed by the plan as providing more than 5% of the total contributions to the plan for the plan years ended December 31, 2018 and 2017.
| (2) | Information for this fund was obtained from the annual funding notice, other notices received from the plan, and the Form 5500 filed for the plan years ended December 31, 2018 and 2017.
| (3) | Adopted a rehabilitation plan effective March 25, 2008 as updated. Utilized amortization extension granted by the IRS effective December 31, 2003.
| (4) | PPA zone status relates to plan years February 1, 2018 – January 31, 2019 and February 1, 2017 – January 31, 2018.
| (5) | The Company was listed by the plan as providing more than 5% of the total contributions to the plan for the plan years ended January 31, 2019 and 2018.
| (6) | Information for this fund was obtained from the annual funding notice, other notices received from the plan, and the Form 5500 filed for the plan years ended January 31, 2019 and 2018.
| (7) | Contributions include $1.6 million and $15.7 million for 2019 and 2018, respectively, related to the multiemployer pension fund withdrawal liability which is further discussed in this Note.
| (8) | Information for this fund was obtained from the annual funding notice, other notices received from the plan, and the Form 5500 filed for the plan years ended September 30, 2018 and 2017.
| (9) | PPA zone status relates to plan years October 1, 2018 – September 30, 2019 and October 1, 2017 – September 30, 2018.
| (10) | Adopted a rehabilitation plan effective January 1, 2009.
| (11) | Contribution levels can be impacted by several factors such as changes in business levels and the related time worked by contractual employees, contractual rate increases for pension benefits, and the specific funding structure, which differs among funds. The 2018 ABF NMFA and the related supplemental agreements provided for contributions to multiemployer pension plans to be frozen at the current rates for each fund. The year-over-year changes in multiemployer pension plan contributions presented above were influenced by the previously mentioned payments related to the New England Pension Fund and changes in Asset-Based business levels.

X
- Definition Tabular disclosure of the fair value of each major category of plan assets, and the level within the fair value hierarchy in which the fair value measurements fall. + References No definition available. + Details
Name: | arcb_ScheduleOfDefinedBenefitPlanFairValueOfPlanAssetsByMajorAssetCategoryAndFairValueHierarchyLevelTableTextBlock
Namespace Prefix: | arcb_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of net funded status of pension plans and/or other employee benefit plans and disclosure of accumulated benefit obligation. + References No definition available. + Details
Name: | arcb_ScheduleOfNetFundedStatusAndChangesInAccumulatedBenefitObligationAndPlanAssetsTableTextBlock
Namespace Prefix: | arcb_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of pension settlement distributions and pension settlement expense related to employee benefit plans. + References No definition available. + Details
Name: | arcb_ScheduleOfPensionSettlementDistributionsAndPensionSettlementExpenseTableTextBlock
Namespace Prefix: | arcb_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_CompensationAndRetirementDisclosureAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of the amounts that are recognized in the balance sheet (or statement of financial position) for pension plans and/or other employee benefit plans, showing separately the assets and current and noncurrent liabilities (if applicable) recognized. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
Name: | us-gaap_ScheduleOfAmountsRecognizedInBalanceSheetTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of assumption used to determine benefit obligation and net periodic benefit cost of defined benefit plan. Includes, but is not limited to, discount rate, rate of compensation increase, expected long-term rate of return on plan assets and interest crediting rate. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
Name: | us-gaap_ScheduleOfAssumptionsUsedTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of benefits expected to be paid by pension plans and/or other employee benefit plans in each of the next five fiscal years and in the aggregate for the five fiscal years thereafter. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
Name: | us-gaap_ScheduleOfExpectedBenefitPaymentsTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of the assumed health care cost trend rates for the next year used to measure the expected cost of benefits covered by the plans, including the ultimate trend rate(s) and when that rate is expected to be achieved. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (l) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
Name: | us-gaap_ScheduleOfHealthCareCostTrendRatesTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of the quantitative and qualitative information related to multiemployer plans in which the employer participates. A multiemployer plan is a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947 + Details
Name: | us-gaap_ScheduleOfMultiemployerPlansTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of the components of net benefit costs for pension plans and/or other employee benefit plans including service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) recognized due to settlements or curtailments. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
Name: | us-gaap_ScheduleOfNetBenefitCostsTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of the amounts related to pension plans and/or other employee benefit plans in accumulated other comprehensive income or loss that have not yet been recognized as components of net periodic benefit cost, such as the net gain (loss), net prior service cost or credit, and net transition asset or obligation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (j) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
Name: | us-gaap_ScheduleOfNetPeriodicBenefitCostNotYetRecognizedTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration