CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
OPERATING ACTIVITIES
NET INCOME	$ 39,866	$ 31,633
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	65,142	60,613
Amortization of intangibles	3,079	3,242
Pension settlement expense	2,478	5,405
Share-based compensation expense	6,343	5,362
Provision for losses on accounts receivable	941	1,647
Deferred income tax benefit	(7,862)	(7,409)
Gain on sale of property and equipment	(1,691)	(597)
Changes in operating assets and liabilities:
Receivables	(14,881)	(41,180)
Prepaid expenses	2,353	1,477
Other assets	505	(1,081)
Income taxes	14,295	9,981
Accounts payable, accrued expenses, and other liabilities	9,006	49,108
NET CASH PROVIDED BY OPERATING ACTIVITIES	119,574	118,201
INVESTING ACTIVITIES
Purchases of property, plant and equipment, net of financings	(53,644)	(23,756)
Proceeds from sale of property and equipment	4,115	2,701
Purchases of short-term investments	(48,868)	(25,347)
Proceeds from sale of short-term investments	25,347	17,478
Business acquisitions, net of cash acquired	(5,239)	(2,647)
Capitalization of internally developed software	(6,155)	(6,016)
NET CASH USED IN INVESTING ACTIVITIES	(84,444)	(37,587)
FINANCING ACTIVITIES
Borrowings under credit facilities	70,000
Borrowings under accounts receivable securitization program	35,000
Payments on long-term debt	(92,136)	(28,024)
Net change in book overdrafts	2,179	2,304
Net change in restricted cash	(1)	517
Deferred financing costs	(824)	(61)
Payment of common stock dividends	(4,740)	(2,458)
Purchase of treasury stock	(10,004)
Proceeds from the exercise of stock options		1,136
NET CASH USED IN FINANCING ACTIVITIES	(526)	(26,586)
NET INCREASE IN CASH AND CASH EQUIVALENTS	34,604	54,028
Cash and cash equivalents at beginning of period	157,042	105,354
CASH AND CASH EQUIVALENTS AT END OF PERIOD	191,646	159,382
NONCASH INVESTING ACTIVITIES
Equipment financed	51,009	41,002
Accruals for equipment received	$ 7,150	$ 9,632