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
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(12))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(11))
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The net result for the period of deducting operating expenses from operating revenues.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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SEGMENT INFORMATION - Summary of Segment Results (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Summarized Information
Sales	$ 2,635,999	$ 2,596,288	$ 7,792,397	$ 7,666,494
Total consolidated operating earnings	281,170	322,587	808,723	945,269
Total assets	5,825,060		5,825,060		$ 5,694,307
UNITED STATES [Member]
Summarized Information
Sales	1,912,301	1,936,075	5,671,318	5,715,943
Total assets	2,316,683		2,316,683		2,275,009
CANADA [Member]
Summarized Information
Sales	188,203	179,258	563,455	552,361
Total assets	298,553		298,553		286,035
Other Businesses [Member]
Summarized Information
Sales	535,495	480,955	1,557,624	1,398,190
Total assets	589,564		589,564		494,067
Segment Balances Before Intersegment Eliminations and Consolidation Reconciling Items [Member]
Summarized Information
Sales	2,741,111	2,689,445	8,092,929	7,926,943
Total consolidated operating earnings	309,775	352,241	907,363	1,044,454
Total assets	3,204,800		3,204,800		$ 3,055,111
Segment Balances Before Intersegment Eliminations and Consolidation Reconciling Items [Member] \| UNITED STATES [Member]
Summarized Information
Sales	2,015,968	2,028,235	5,968,565	5,973,044
Total consolidated operating earnings	297,855	342,524	922,614	1,023,318
Segment Balances Before Intersegment Eliminations and Consolidation Reconciling Items [Member] \| CANADA [Member]
Summarized Information
Sales	188,216	179,281	563,470	552,470
Total consolidated operating earnings	(14,972)	(15,118)	(59,428)	(55,207)
Segment Balances Before Intersegment Eliminations and Consolidation Reconciling Items [Member] \| Other Businesses [Member]
Summarized Information
Sales	536,927	481,929	1,560,894	1,401,429
Total consolidated operating earnings	26,892	24,835	44,177	76,343
Intersegment Eliminations [Member]
Summarized Information
Sales	(105,112)	(93,157)	(300,532)	(260,449)
Intersegment Eliminations [Member] \| UNITED STATES [Member]
Summarized Information
Sales	(103,667)	(92,160)	(297,247)	(257,101)
Intersegment Eliminations [Member] \| CANADA [Member]
Summarized Information
Sales	(13)	(23)	(15)	(109)
Intersegment Eliminations [Member] \| Other Businesses [Member]
Summarized Information
Sales	$ (1,432)	$ (974)	$ (3,270)	$ (3,239)