Amount of distribution received from equity method investee for return on investment, classified as operating activities. Excludes distribution for return of investment, classified as investing activities.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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For an unclassified balance sheet, reflects the carrying amount of unpaid loan amounts due from related parties at the balance sheet date.

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The difference between the carrying value and the sale price of an investment. A loss would be recognized when the sale price of the investment is less than the carrying value of the investment. This element refers to the Loss included in earnings and not to the cash proceeds of the sale.

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The cash inflow from the sale of an investment interest in a joint venture that the reporting entity has not previously accounted for using consolidation or the equity method of accounting.

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Amount of consolidated retained earnings that represent undistributed (not yet received) earnings from 50% or less owned persons accounted for by the equity method (equity method investees).

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Percentage of subsidiary's or equity investee's stock owned by parent company before stock transaction.

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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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Equity Method Investment, Contingent Consideration Arrangements, Second Performance Period, Range of Outcomes, Value, High

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Equity Method Investment, Performance Target

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Loss On Sale Of Investments, Net Of Tax

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Equity Method Investments - Narrative (Details) - USD ($)	3 Months Ended	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Schedule of Equity Method Investments [Line Items]
Dividends received from equity method investments		$ 16,000,000	$ 23,000,000
Equity method investment, performance target		5 years
Interest of joint venture	33.00%
Sale of interest in joint venture	$ 3,000,000
Loss on sale of investment	8,000,000
Loss on sale of investments, net of tax	5,000,000
USG Boral Building Products
Schedule of Equity Method Investments [Line Items]
Loan receivable from related party	$ 13,000,000	$ 13,000,000		$ 13,000,000
USG Boral Building Products
Schedule of Equity Method Investments [Line Items]
Joint venture (percentage)	50.00%	50.00%		50.00%
Dividends received from equity method investments	$ 16,000,000
Undistributed earnings	66,000,000	$ 66,000,000
Contingent consideration for second performance period	$ 50,000,000	$ 50,000,000