Condensed Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Cash flows from operating activities:
Net income	$ 40,942	$ 34,782
Adjustments to reconcile net income to cash flows provided by operating activities:
Depreciation and amortization	19,855	14,920
Stock-based compensation expense	7,069	5,277
Other non-cash items	162	3,203
Changes in assets and liabilities, net of acquisitions of businesses:
Accounts receivable, net	(30,536)	(36,920)
Inventories, net	(24,361)	(1,227)
Prepaid expenses and other assets	2,333	(687)
Accounts payable, trade	1,250	23,095
Accrued expenses and other liabilities	19,645	13,352
Net cash flows provided by operating activities	36,359	55,795
Cash flows from investing activities:
Capital expenditures	(14,668)	(17,912)
Acquisitions of businesses	(25,058)	(82,157)
Proceeds from note receivable	0	750
Proceeds from sales of fixed assets	1,958	1,999
Other investing activities	(213)	(49)
Net cash flows used for investing activities	(37,981)	(97,369)
Cash flows from financing activities:
Exercise of stock-based awards, net of shares tendered for payment of taxes	(688)	3,425
Proceeds from line of credit borrowings	390,870	182,315
Repayments under line of credit borrowings	(376,520)	(160,027)
Proceeds from shelf-loan borrowing	50,000	0
Payment of special dividend	(48,227)	(46,706)
Payment of contingent consideration related to acquisitions	(1,874)	(3,513)
Other financing activities	(161)	(196)
Net cash flows provided by (used for) financing activities	13,400	(24,702)
Net increase (decrease) in cash	11,778	(66,276)
Cash and cash equivalents at beginning of period	4	66,280
Cash and cash equivalents at end of period	11,782	4
Cash paid during the period for:
Interest	788	204
Income taxes, net of refunds	$ 8,613	$ 13,297