Income Taxes Deferred tax assets and liabilties (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Income Taxes [Abstract]
Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Allowance for Doubtful Accounts	$ 262	$ 224
Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Accrued Liabilities	3,892	3,179
Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Share-based Compensation Cost	178	92
Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Self Insurance	15,054	15,415
Deferred Tax Assets Operating Loss Carryforwards - State	2,618	0
Deferred Tax Assets Operating Loss Carryforwards - Federal	8,793	0
Unrecognized tax benefit	1,052	963
Deferred Tax Assets, Other	3	2
Deferred Tax Assets, Gross	31,852	19,875
Deferred Tax Assets, Valuation Allowance	0	0
Deferred Tax Assets, Net	31,852	19,875
Deferred Tax Liabilities, Property, Plant and Equipment	(101,843)	(74,794)
Deferred Tax Liabilities, Goodwill and Intangible Assets	(15,939)	(10,319)
Deferred Tax Liabilities, Prepaid Expenses	(1,762)	(1,268)
Deferred Income Tax Liabilities	(119,544)	(86,381)
Deferred Tax Liabilities, Net	$ (87,692)	$ (66,506)