Unaudited Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 29, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 2,545	$ 1,672
Marketable securities	10,433	15,144
Accounts receivable – net of allowance for doubtful accounts of $1,602 and $1,330, respectively	214,712	171,036
Other receivables	17,662	17,511
Due from affiliates	3,221	2,685
Prepaid income taxes		4,515
Prepaid expenses and other	25,825	16,103
Total current assets	274,398	228,666
Property and equipment – net of accumulated depreciation of $227,146 and $205,771, respectively	298,633	267,195
Goodwill	114,097	74,484
Intangible assets – net of accumulated amortization of $60,113 and $56,901, respectively	75,844	31,259
Deferred income taxes	2,616	4,154
Other assets	3,372	4,834
Total assets	768,960	610,592
Current liabilities:
Accounts payable	106,999	84,380
Due to affiliates	15,174	11,964
Accrued expenses and other current liabilities	27,317	24,129
Income taxes payable	2,826
Insurance and claims	33,018	37,727
Current portion of long-term debt	84,956	40,870
Total current liabilities	270,290	199,070
Long-term liabilities:
Long-term debt, net of current portion	244,305	207,108
Deferred income taxes	45,317	32,361
Other long-term liabilities	4,327	3,288
Total long-term liabilities	293,949	242,757
Shareholders' equity:
Common stock, no par value. Authorized 100,000,000 shares; 30,954,202 and 30,941,702 shares issued; 28,371,327 and 28,382,392 shares outstanding, respectively	30,955	30,943
Paid-in capital	4,074	3,841
Treasury stock, at cost; 2,582,875 and 2,559,310 shares, respectively	(52,364)	(51,532)
Retained earnings	225,485	186,226
Accumulated other comprehensive income (loss):
Unrealized holding gain on available-for-sale securities, net of income taxes of $0 and $1,090, respectively		3,823
Interest rate swaps, net of income taxes of $170 and $63, respectively	540	197
Foreign currency translation adjustments	(3,969)	(4,733)
Total shareholders’ equity	204,721	168,765
Total liabilities and shareholders’ equity	$ 768,960	$ 610,592