CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Cash flows from operating activities
Net income	$ 22,029	$ 20,350
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation expense	14,982	12,445
Amortization of intangible assets	5,013	4,347
Amortization of debt issuance costs	317	421
Deferred income taxes	10,297	6,771
Non-cash stock compensation expense	3,170	2,915
Gain on sale of property, equipment and real estate	(143)	(913)
Other non-cash adjustments	0	1,778
Change in assets and liabilities, net of effects of acquisitions
Accounts receivable, net of allowances	(26,031)	(9,463)
Inventories	(29,680)	1,499
Accounts payable	43,277	69,741
Other assets and liabilities	(26,165)	(32,132)
Net cash provided by operating activities	17,066	77,759
Cash flows from investing activities
Purchases of businesses, net of cash acquired	0	(52,012)
Purchases of property, equipment and real estate	(30,509)	(15,429)
Proceeds from sale of property, equipment and real estate	349	2,343
Net cash used in investing activities	(30,160)	(65,098)
Cash flows from financing activities
Proceeds from revolving credit facility	144,000	110,987
Repayments of proceeds from revolving credit facility	0	(110,987)
Repurchases of common stock under share repurchase program	(1,416)	(15,219)
Payments on finance lease obligations	(1,628)	(1,708)
Other financing activities, net	(10,543)	(4,875)
Net cash provided by (used in) financing activities	130,413	(21,802)
Net increase (decrease) in cash and cash equivalents	117,319	(9,141)
Cash and cash equivalents
Beginning of period	165,496	150,723
End of period	282,815	141,582
Supplemental disclosure of non-cash investing and financing transactions
Accrued purchases of property and equipment	7,236	7,613
Acquisition-related holdback payments due at future date	4,990	2,500
Accrued repurchases of common stock under share repurchase program	$ 0	$ 490