Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Operating activities:
Net income	$ 135,601	$ 121,380	$ 118,370
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	80,154	78,242	81,395
Amortization of convertible debt discount	0	0	731
(Gain) loss on disposition of property, plant and equipment	(349)	(1,128)	143
Stock compensation expense	11,493	9,258	7,603
Loss on the sale of businesses	0	0	(1,586)
Pension lump-sum settlement charge	0	9,856	0
Changes in assets and liabilities, net of the effects of acquisitions:
Accounts receivable	(23,057)	14,027	(21,367)
Inventories	1,989	(1,190)	(10,092)
Prepaid expenses and other current assets	569	(2,645)	(7,137)
Accounts payable	11,778	(2,936)	8,123
Accrued liabilities	15,825	(14,166)	29,290
Deferred income taxes	(2,210)	3,121	(9,841)
Long-term retirement benefits	(15,492)	1,081	(7,584)
Other	1,345	2,575	4,933
Net cash provided by operating activities	217,646	217,475	196,153
Investing activities:
Proceeds from disposition of property, plant and equipment	780	3,442	849
Payments for the sale of businesses	0	0	(1,181)
Change in restricted cash	0	0	4,886
Capital expenditures	(47,577)	(45,982)	(57,365)
Business acquisitions, net of cash acquired	(128,613)	(51,954)	0
Component Repair Program payments	(4,100)	(21,000)	(70,100)
Other	0	0	(1,338)
Net cash used in investing activities	(179,510)	(115,494)	(124,249)
Financing activities:
Net change in other borrowings	8,375	14,680	7,009
Payments on long-term debt	(321,506)	(171,198)	(332,336)
Proceeds from the issuance of long-term debt	303,277	159,264	293,291
Payment of assumed liability to Otto Männer Holding AG	0	0	(19,796)
Premium paid on convertible debt redemption	0	0	(14,868)
Proceeds from the issuance of common stock	4,611	11,425	11,460
Common stock repurchases	(20,520)	(52,103)	(8,389)
Dividends paid	(27,435)	(26,176)	(24,464)
Withholding taxes paid on stock issuances	(4,885)	(4,913)	(4,367)
Other	4,771	9,850	(338)
Net cash used by financing activities	(53,312)	(59,171)	(92,798)
Effect of exchange rate changes on cash flows	(2,303)	(4,923)	(3,923)
(Decrease) increase in cash and cash equivalents	(17,479)	37,887	(24,817)
Cash and cash equivalents at beginning of year	83,926	46,039	70,856
Cash and cash equivalents at end of year	$ 66,447	83,926	46,039
Supplemental Disclosure of Cash Flow Information:
Intangible assets acquired		$ 3,200	$ 19,000