Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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The net result for the period of deducting operating expenses from operating revenues.

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The cash outflow for purchases of and capital improvements on property, plant and equipment (capital expenditures), software, and other intangible assets.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Business Segment Information (Reportable Segments) (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2017 USD ($) segments	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Segment Reporting Information [Line Items]
Number of operating segments (in segments) \| segments									3
Summarized financial information of the reportable segments
Sales to external customers	$ 1,034,100	$ 883,400	$ 877,100	$ 866,300	$ 1,071,000	$ 945,900	$ 1,027,400	$ 946,200	$ 3,660,831	$ 3,990,487	$ 4,557,791
Intersegment sales									0	0	0
Segment operating income (loss)									335,422	267,965	514,665
Depreciation and amortization									118,454	116,752	127,087
Identifiable assets	4,910,474				4,708,923				4,910,474	4,708,923	4,963,106
Capital expenditures									61,602	89,699	181,861
Subtotal—Reportable Segments
Summarized financial information of the reportable segments
Sales to external customers									3,660,831	3,990,487	4,557,791
Intersegment sales									77,917	74,263	96,234
Segment operating income (loss)									428,585	359,670	582,724
Depreciation and amortization									104,801	105,970	117,519
Identifiable assets	4,302,837				4,403,109				4,302,837	4,403,109	4,610,292
Capital expenditures									44,784	73,229	171,511
Engineered Product Division
Summarized financial information of the reportable segments
Sales to external customers									1,738,082	1,963,086	2,209,809
Intersegment sales									37,347	32,873	46,821
Segment operating income (loss)									156,830	167,420	319,980
Depreciation and amortization									48,659	48,957	50,289
Identifiable assets	1,956,638				2,082,729				1,956,638	2,082,729	2,230,134
Capital expenditures									19,790	29,426	88,496
Industrial Product Division
Summarized financial information of the reportable segments
Sales to external customers									739,656	799,923	937,756
Intersegment sales									35,552	35,156	44,137
Segment operating income (loss)									(49,475)	(6,370)	29,128
Depreciation and amortization									28,864	28,824	36,826
Identifiable assets	1,028,255				1,010,107				1,028,255	1,010,107	1,056,400
Capital expenditures									8,368	17,336	19,446
Flow Control Division [Member]
Summarized financial information of the reportable segments
Sales to external customers									1,183,093	1,227,478	1,410,226
Intersegment sales									5,018	6,234	5,276
Segment operating income (loss)									321,230	198,620	233,616
Depreciation and amortization									27,278	28,189	30,404
Identifiable assets	1,317,944				1,310,273				1,317,944	1,310,273	1,323,758
Capital expenditures									16,626	26,467	63,569
Intersegment Eliminations [Member]
Summarized financial information of the reportable segments
Sales to external customers									0	0	0
Intersegment sales									(77,917)	(74,263)	(96,234)
Segment operating income (loss)									(93,163)	(91,705)	(68,059)
Depreciation and amortization									13,653	10,782	9,568
Identifiable assets	$ 607,637				$ 305,814				607,637	305,814	352,814
Capital expenditures									$ 16,818	$ 16,470	$ 10,350