CONDENSED CONSOLIDATED STATEMENT OF SHAREHOLDERS EQUITY Statement - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Treasury Stock [Member]	AOCI Attributable to Parent [Member]	Retained Earnings [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock, shares outstanding (shares)		123.061
Stockholders' Equity Attributable to Parent at Dec. 31, 2017	$ 3,460,000	$ 1,000	$ 164,000	$ (518,000)	$ (380,000)	$ 4,193,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	4,000					4,000
Other Comprehensive Income (Loss), Net of Tax	2,000				2,000
Stock repurchased during period (shares)		(0.186)
Stock Repurchased During Period, Value	(13,000)		0	(13,000)
Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition	12,000		12,000
Dividends, Cash	(40,000)					(40,000)
Stock Issued During Period, Shares, Employee Stock Purchase Plans		0.312
Stock Issued During Period, Shares, Share-based Compensation, Net of Forfeitures		0.163
Stock Issued During Period, Value, Employee Stock Purchase Plan	17,000		17,000
Stock Issued During Period, Value, Share-based Compensation, Net of Forfeitures	(3,000)		(3,000)
Stockholders' Equity Attributable to Parent at Mar. 31, 2018	3,439,000	$ 1,000	190,000	(531,000)	(440,000)	4,219,000
Stockholders' Equity Attributable to Parent at Dec. 31, 2017	3,460,000	1,000	164,000	(518,000)	(380,000)	4,193,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	414,000
Other Comprehensive Income (Loss), Net of Tax	14,000
Stockholders' Equity Attributable to Parent at Sep. 30, 2018	3,791,000	$ 1,000	224,000	(556,000)	(428,000)	4,550,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock, shares outstanding (shares)		123.350
Stockholders' Equity Attributable to Parent at Mar. 31, 2018	3,439,000	$ 1,000	190,000	(531,000)	(440,000)	4,219,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	193,000					193,000
Other Comprehensive Income (Loss), Net of Tax	5,000				5,000
Stock repurchased during period (shares)		(0.204)
Stock Repurchased During Period, Value	(13,000)			(13,000)
Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition	9,000		9,000
Dividends, Cash	(39,000)					(39,000)
Stock Issued During Period, Shares, Share-based Compensation, Net of Forfeitures		0.058
Stock Issued During Period, Value, Share-based Compensation, Net of Forfeitures	(1,000)		(1,000)
Stockholders' Equity Attributable to Parent at Jun. 30, 2018	3,593,000	$ 1,000	198,000	(544,000)	(435,000)	4,373,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock, shares outstanding (shares)		123.204
Net Income	217,000					217,000
Other Comprehensive Income (Loss), Net of Tax	7,000				7,000
Stock repurchased during period (shares)		(0.193)
Stock Repurchased During Period, Value	(12,000)		0	(12,000)
Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition	8,000		8,000
Dividends, Cash	$ (40,000)					(40,000)
Cash dividend declared per share (usd per share)	$ 0.32
Stock Issued During Period, Shares, Employee Stock Purchase Plans		0.320
Stock Issued During Period, Shares, Share-based Compensation, Net of Forfeitures		0.030
Stock Issued During Period, Value, Employee Stock Purchase Plan	$ 18,000		18,000
Stock Issued During Period, Value, Share-based Compensation, Net of Forfeitures	0		0
Stockholders' Equity Attributable to Parent at Sep. 30, 2018	$ 3,791,000	$ 1,000	224,000	(556,000)	(428,000)	4,550,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock, shares outstanding (shares)		123.361
Common stock, shares outstanding (shares)	123,194,430	123.194
Stockholders' Equity Attributable to Parent at Dec. 31, 2018	$ 3,751,000	$ 1,000	232,000	(568,000)	(448,000)	4,534,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	4,000					4,000
Other Comprehensive Income (Loss), Net of Tax	15,000				15,000
Stock repurchased during period (shares)		(0.215)
Stock Repurchased During Period, Value	(13,000)		0	(13,000)
Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition	12,000		12,000
Dividends, Cash	(43,000)					(43,000)
Stock Issued During Period, Shares, Employee Stock Purchase Plans		0.391
Stock Issued During Period, Shares, Share-based Compensation, Net of Forfeitures		0.134
Stock Issued During Period, Value, Employee Stock Purchase Plan	20,000		20,000
Stock Issued During Period, Value, Share-based Compensation, Net of Forfeitures	(3,000)		(3,000)
Stockholders' Equity Attributable to Parent at Mar. 31, 2019	3,746,000	$ 1,000	261,000	(581,000)	(433,000)	4,498,000
Stockholders' Equity Attributable to Parent at Dec. 31, 2018	3,751,000	1,000	232,000	(568,000)	(448,000)	4,534,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	588,000
Other Comprehensive Income (Loss), Net of Tax	27,000
Stockholders' Equity Attributable to Parent at Sep. 30, 2019	4,252,000	$ 1,000	297,000	(621,000)	(421,000)	4,996,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative Effect of New Accounting Principle in Period of Adoption	3,000					3,000
Common stock, shares outstanding (shares)		123.504
Stockholders' Equity Attributable to Parent at Mar. 31, 2019	3,746,000	$ 1,000	261,000	(581,000)	(433,000)	4,498,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	262,000					262,000
Other Comprehensive Income (Loss), Net of Tax	11,000				11,000
Stock repurchased during period (shares)		(0.194)
Stock Repurchased During Period, Value	(12,000)		0	(12,000)
Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition	9,000		9,000
Dividends, Cash	(43,000)					(43,000)
Stock Issued During Period, Shares, Employee Stock Purchase Plans		0.028
Stock Issued During Period, Value, Share-based Compensation, Net of Forfeitures	0
Stockholders' Equity Attributable to Parent at Jun. 30, 2019	3,973,000	$ 1,000	270,000	(593,000)	(422,000)	4,717,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock, shares outstanding (shares)		123.338
Net Income	322,000					322,000
Other Comprehensive Income (Loss), Net of Tax	1,000				1,000
Stock repurchased during period (shares)		(0.465)
Stock Repurchased During Period, Value	(28,000)		0	(28,000)
Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition	7,000		7,000
Dividends, Cash	$ (43,000)					(43,000)
Cash dividend declared per share (usd per share)	$ 0.35
Stock Issued During Period, Shares, Employee Stock Purchase Plans		0.394
Stock Issued During Period, Shares, Share-based Compensation, Net of Forfeitures		0.011
Stock Issued During Period, Value, Employee Stock Purchase Plan	$ 20,000		20,000
Stock Issued During Period, Value, Share-based Compensation, Net of Forfeitures	0		0
Stockholders' Equity Attributable to Parent at Sep. 30, 2019	$ 4,252,000	$ 1,000	$ 297,000	$ (621,000)	$ (421,000)	$ 4,996,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock, shares outstanding (shares)	123,277,911	123.278