Consolidated Statement Of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Cash Flows from Operating Activities
Net income	$ 24,840	$ 24,537
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	8,516	8,159
Benefit for deferred income taxes	(4,202)	(2,734)
Provision for uncollectible accounts receivable	4,242	3,804
Stock option expense	2,563	1,444
Amortization of restricted stock awards	539	449
Amortization of debt issuance costs	130	131
Noncash long-term incentive compensation	(305)	934
Changes in operating assets and liabilities:
Increase in accounts receivable	(41,050)	(24,926)
Decrease in inventories	212	2
Decrease in prepaid expenses	546	1,433
Decrease in accounts payable and other current liabilities	(7,567)	(9,538)
Decrease in income taxes	19,448	11,696
Decrease/(increase) in other assets	410	(2,815)
Increase/(decrease) in other liabilities	(140)	2,569
Excess tax benefit on share-based compensation	(900)	(2,900)
Other sources/(uses)	(59)	129
Net cash provided by operating activities	7,223	12,374
Cash Flows from Investing Activities
Capital expenditures	(11,473)	(8,553)
Other sources	153	351
Net cash used by investing activities	(11,320)	(8,202)
Cash Flows from Financing Activities
Proceeds from long-term debt	59,000	37,200
Payments on revolving line of credit	(3,500)	(22,200)
Payments on other long-term debt	(1,875)	(1,250)
Purchases of treasury stock	(52,460)
Proceeds from exercise of stock options (Note 4)	2,887	4,899
Dividends paid	(4,081)	(3,743)
Capital stock surrendered to pay taxes on stock-based compensation	(4,020)	(5,464)
Excess tax benefit on stock-based compensation	900	2,900
Increase/(decrease) in cash overdraft payable	7,061	(1,528)
Other sources/(uses)	693	(783)
Net cash provided by financing activities	4,605	10,031
Increase in Cash and Cash Equivalents	508	14,203
Cash and cash equivalents at beginning of year	14,727	14,132
Cash and cash equivalents at end of year	$ 15,235	$ 28,335