Condensed Consolidated Statements of Changes in Stockholders' Equity (Unaudited) - USD ($) shares in Millions, $ in Millions	Total	Total Stockholders Equity	Common Stock	Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive (Loss) Income	Non-Redeemable Noncontrolling Interests in Subsidiaries
Balance at beginning of period (in shares) at Dec. 31, 2018			119.0
Balance at beginning of period at Dec. 31, 2018		$ 399	$ 1	$ 34	$ 606	$ (246)	$ 4
Comprehensive income:
Net income		38			37		1
Other comprehensive income		16				16
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Nonredeemable Noncontrolling Interest		54			37	16	1
Employee stock purchase and stock compensation plans (in shares)			1.0
Employee stock purchase and stock compensation plans		14		14
Series A convertible preferred stock dividends		(13)			(13)
Balance at end of period (in shares) at Mar. 31, 2019			120.0
Balance at end of period at Mar. 31, 2019		454	$ 1	48	630	(230)	5
Balance at beginning of period (in shares) at Dec. 31, 2018			119.0
Balance at beginning of period at Dec. 31, 2018		399	$ 1	34	606	(246)	4
Comprehensive income:
Other comprehensive income	$ 5
Balance at end of period (in shares) at Jun. 30, 2019			120.0
Balance at end of period at Jun. 30, 2019		547	$ 1	76	706	(241)	5
Balance at beginning of period (in shares) at Mar. 31, 2019			120.0
Balance at beginning of period at Mar. 31, 2019		454	$ 1	48	630	(230)	5
Comprehensive income:
Net income		88			88
Other comprehensive income	$ (11)	(11)				(11)
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Nonredeemable Noncontrolling Interest		77			88	(11)
Employee stock purchase and stock compensation plans		28		28
Series A convertible preferred stock dividends		(12)			(12)
Repurchase of Company common stock		0		0	0
Balance at end of period (in shares) at Jun. 30, 2019			120.0
Balance at end of period at Jun. 30, 2019		547	$ 1	76	706	(241)	5
Balance at beginning of period (in shares) at Dec. 31, 2019	127.7		127.0
Balance at beginning of period at Dec. 31, 2019	$ 1,107	1,107	$ 1	312	1,060	(269)	3
Comprehensive income:
Net income		24			23		1
Other comprehensive income		(61)				(60)	(1)
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Nonredeemable Noncontrolling Interest		(37)			23	(60)	0
Employee stock purchase and stock compensation plans (in shares)			2.0
Employee stock purchase and stock compensation plans		4		4
Series A convertible preferred stock dividends		(6)			(6)
Repurchase of Company common stock (in shares)			(2.0)
Repurchase of Company common stock		(41)		(41)
Balance at end of period (in shares) at Mar. 31, 2020			127.0
Balance at end of period at Mar. 31, 2020		1,027	$ 1	275	1,077	(329)	3
Balance at beginning of period (in shares) at Dec. 31, 2019	127.7		127.0
Balance at beginning of period at Dec. 31, 2019	$ 1,107	1,107	$ 1	312	1,060	(269)	3
Comprehensive income:
Other comprehensive income	$ (47)
Balance at end of period (in shares) at Jun. 30, 2020	128.2		128.0
Balance at end of period at Jun. 30, 2020	$ 1,123	1,123	$ 1	300	1,134	(315)	3
Balance at beginning of period (in shares) at Mar. 31, 2020			127.0
Balance at beginning of period at Mar. 31, 2020		1,027	$ 1	275	1,077	(329)	3
Comprehensive income:
Net income		64			64
Other comprehensive income	$ 14	14				14
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Nonredeemable Noncontrolling Interest		78			64	14
Employee stock purchase and stock compensation plans (in shares)			1.0
Employee stock purchase and stock compensation plans		25		25
Series A convertible preferred stock dividends		(7)			(7)
Balance at end of period (in shares) at Jun. 30, 2020	128.2		128.0
Balance at end of period at Jun. 30, 2020	$ 1,123	$ 1,123	$ 1	$ 300	$ 1,134	$ (315)	$ 3