Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2019	Mar. 31, 2018
Operating activities
Net income		$ 45,769	$ 33,770
Adjustment to reconcile net income to net cash provided by operating activities:
Depreciation		7,265	6,051
Amortization of intangible assets		5,342	5,632
Amortization of original issue discount and deferred financing costs		1,177	1,177
Deferred income taxes		5,151	4,283
Share-based compensation expense	[1]	3,594	3,106
Other		66	102
Net changes in operating assets and liabilities, net of acquisitions:
Accounts receivable		46,970	18,744
Inventories		(41,644)	(48,798)
Other assets		(1,293)	2,658
Accounts payable		(37,176)	(9,439)
Accrued wages and employee benefits		(14,148)	813
Other accrued liabilities		(5,762)	11,065
Excess tax benefits from equity awards		(740)	(196)
Net cash provided by operating activities		14,571	28,968
Investing activities
Proceeds from sale of property and equipment		23	1
Proceeds from beneficial interests in securitization transactions		743	867
Expenditures for property and equipment		(15,902)	(6,496)
Acquisition of business, net of cash acquired		(61,549)	(369)
Net cash used in investing activities		(76,685)	(5,997)
Financing activities
Proceeds from short-term borrowings		13,531	14,315
Repayments of short-term borrowings		(13,282)	(3,911)
Repayments of long-term borrowings and finance lease obligations		(908)	(408)
Stock repurchases			(25,656)
Cash dividends paid to noncontrolling interest of subsidiary			(314)
Taxes paid related to equity awards		(3,156)	(1,626)
Proceeds from exercise of stock options		2,193	1,400
Net cash used in financing activities		(1,622)	(16,200)
Effect of exchange rate changes on cash and cash equivalents		520	919
Net (decrease) increase in cash and cash equivalents		(63,216)	7,690
Cash and cash equivalents at beginning of period		224,482	138,472
Cash and cash equivalents at end of period		$ 161,266	$ 146,162

[1] Represents share-based compensation expense to account for stock options, restricted stock and other stock awards over their respective vesting periods.