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Subsidiary Total Assets as a Percentage of Consolidated Assets

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The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

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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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Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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

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Amount of income (expense) related to nonoperating activities, classified as other.

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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

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Basis of Presentation and Accounting Policies (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Jan. 01, 2018	Dec. 31, 2017
Financial Statement Line Items with Differences in Reported Amount and Reporting Currency Denominated Amounts [Line Items]
Subsidiary sales as a percentage of consolidated sales	1.00%		1.00%
Subsidiary total assets as a percentage of consolidated assets	1.00%		1.00%
Retained earnings	$ 3,502,006		$ 3,502,006		$ 3,523,589	$ 3,503,947
Cost of sales	(687,072)	$ (631,603)	(1,335,593)	$ (1,228,934)
Gross profit	286,057	245,460	557,490	514,447
Selling, general and administrative expense	(240,791)	(252,530)	(469,966)	(474,304)
Segment operating income (loss)	46,711	126,878	92,137	177,546
Other expense, net	(4,770)	(9,496)	(11,925)	(21,483)
Accounting Standard Update 2017-07 Compensation Retirement Benefit topic 715
Financial Statement Line Items with Differences in Reported Amount and Reporting Currency Denominated Amounts [Line Items]
Cost of sales		465		1,014
Gross profit		465		1,014
Selling, general and administrative expense		270		581
Segment operating income (loss)		735		1,595
Other expense, net		(735)		(1,595)
Difference between Revenue Guidance in Effect before and after Topic 606 \| Accounting Standards Update 2014-09
Financial Statement Line Items with Differences in Reported Amount and Reporting Currency Denominated Amounts [Line Items]
Retained earnings	33,038		33,038			$ 19,642
Cost of sales	(2,323)		(66,369)
Gross profit	8,176		14,855
Selling, general and administrative expense	(60)		0
Segment operating income (loss)	8,116		14,855
Other expense, net	$ (90)		$ (301)
Previously Reported \| Accounting Standard Update 2017-07 Compensation Retirement Benefit topic 715
Financial Statement Line Items with Differences in Reported Amount and Reporting Currency Denominated Amounts [Line Items]
Cost of sales		(632,068)		(1,229,948)
Gross profit		244,995		513,433
Selling, general and administrative expense		(252,800)		(474,885)
Segment operating income (loss)		126,143		175,951
Other expense, net		$ (8,761)		$ (19,888)