Equity (Tables)

3 Months Ended

Mar. 31, 2018

Equity [Abstract]

Schedule of Stockholders Equity [Table Text Block]

The activity in equity during the three months ended March 31, 2018 and 2017 is as follows (dollars in millions):

	Common Stock				Accumulated Other Comprehensive Loss			Retained Earnings
	Shares	Amount									Total
Balances as of December 31, 2017	89,114,265	$	1,207		$	(8	)	$	1,217		$	2,416
Issuances of shares pursuant to equity-based plans	99,854	—			—			—			—
Stock-based compensation	—	(1		)	—			—			(1		)
Dividends declared	—	—			—			(30		)	(30		)
Net income	—	—			—			64			64
Balances as of March 31, 2018	89,214,119	$	1,206		$	(8	)	$	1,251		$	2,449
Balances as of December 31, 2016	88,946,704	$	1,201		$	(7	)	$	1,150		$	2,344
Issuances of shares pursuant to equity-based plans	121,154	—			—			—			—
Stock-based compensation	—	(1		)	—			—			(1		)
Dividends declared	—	—			—			(28		)	(28		)
Other comprehensive income (loss)	—	—			(1		)	—			(1		)
Net income	—	—			—			73			73
Balances as of March 31, 2017	89,067,858	$	1,200		$	(8	)	$	1,195		$	2,387