Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Taxes [Abstract]
Corporate tax rate		21.00%	35.00%
Deferred tax assets and liabilities expected to reverse, percentage		25.00%
Additional provision for income tax expense	$ 5,900	$ 5,868
Current [Abstract]
Federal		8,422	$ 14,239	$ 16,259
State		2,118	2,350	2,326
Current income tax expense (benefit)		10,540	16,589	18,585
Deferred [Abstract]
Federal		(232)	5,829	(690)
State		(207)	(270)	(430)
Deferred income tax expense (benefit)		(439)	5,559	(1,120)
Income tax expense (benefit)		10,101	22,148	17,465
Effective income tax rate reconciliation [Abstract]
Statutory rates applied to income before income taxes		8,486	15,129	16,037
State income taxes, net of Federal tax benefit		1,616	1,306	1,494
Net permanent differences		220	95	99
Other		(221)	(250)	(165)
Tax Act, net impact		0	5,868	0
Income tax expense (benefit)		10,101	22,148	$ 17,465
Deferred tax assets [Abstract]
Accounts receivable	433	530	433
Property and equipment	6,434	7,584	6,434
Leases	4,356	4,135	4,356
Accrued liabilities	8,171	8,172	8,171
Retirement benefits	492	266	492
Other	62	56	62
Total deferred tax assets	19,948	20,743	19,948
Deferred tax liabilities [Abstract]
Inventory	7,034	7,649	7,034
Other	539	550	539
Total deferred tax liabilities	7,573	8,199	7,573
Net deferred tax assets	$ 12,375	$ 12,544	$ 12,375

Percentage of reported income tax expense (benefit) in excess of (less than) expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operations, attributable to increase (decrease) in income tax rate and transition tax on accumulated earnings of controlled foreign corporation deemed repatriated pursuant to Tax Cuts and Jobs Act of 2017.

No definition available.