Acquisitions of Millis Transfer and Interstate Distributor Co. (Tables)

12 Months Ended

Dec. 31, 2019

Business Combinations [Abstract]

Business Acquisition, Pro Forma Information [Text Block]

	Year ended	Year ended
	December 31, 2019	December 31, 2018
	(in thousands)
Operating revenue	$694,672	$760,917
Net income	$75,951	$76,259

Business Acquisition ProForma Information

	Year ended
	December 31, 2017
	(in thousands)
Operating revenue	$	756,498
Net income	$	72,752

Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block]

MILLIS TRANSFER ACQUISITION DATE FAIR MARKET VALUES	(in thousands)
Trade and other accounts receivable	$	14,474
Other current assets	1,656
Property and equipment	117,060
Other non-current assets	802
Intangible assets	15,300
Goodwill	35,885
Total assets	185,177
Accounts payable, accrued expenses, and current portion of long-term debt	(31,737)
Insurance accruals	(4,371)
Long-term debt	(70,191)
Deferred taxes	(16,201)
Total cash paid and common stock issued	$	62,677

Schedule of Business Acquisitions, by Acquisition [Table Text Block]

MILLIS TRANSFER TOTAL PURCHASE PRICE CONSIDERATION	(in thousands)
Cash paid pursuant to Stock Purchase Agreement	$	61,927
Common stock issued pursuant to the Acquisition and Merger Agreement	750
Total cash paid and common stock issued	$	62,677