CONSOLIDATED CONDENSED STATEMENTS OF SHAREOWNER'S EQUITY - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In- Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)
Beginning Balance at Dec. 31, 2017	$ 7,127,199	$ 0	$ 5,554,059	$ 1,560,444	$ 12,696
Increase (decrease) in shareowners' equity
Net income	74,112			74,112
Other comprehensive income (loss)	(576,444)				(576,444)
Comprehensive income (loss)	(502,332)
Dividends to parent	(140,000)			(140,000)
Ending Balance at Mar. 31, 2018	6,392,342	0	5,554,059	1,412,583	(574,300)
Beginning Balance at Dec. 31, 2017	7,127,199	0	5,554,059	1,560,444	12,696
Increase (decrease) in shareowners' equity
Net income	265,707
Other comprehensive income (loss)	(1,204,851)
Comprehensive income (loss)	(939,144)
Ending Balance at Sep. 30, 2018	5,955,530	0	5,554,059	1,604,178	(1,202,707)
Beginning Balance at Mar. 31, 2018	6,392,342	0	5,554,059	1,412,583	(574,300)
Increase (decrease) in shareowners' equity
Net income	81,495			81,495
Other comprehensive income (loss)	(429,405)				(429,405)
Comprehensive income (loss)	(347,910)
Ending Balance at Jun. 30, 2018	6,044,432	0	5,554,059	1,494,078	(1,003,705)
Increase (decrease) in shareowners' equity
Net income	110,100			110,100
Other comprehensive income (loss)	(199,002)				(199,002)
Comprehensive income (loss)	(88,902)
Ending Balance at Sep. 30, 2018	5,955,530	0	5,554,059	1,604,178	(1,202,707)
Beginning Balance at Dec. 31, 2018	5,767,734	0	5,554,059	1,639,441	(1,425,766)
Increase (decrease) in shareowners' equity
Net income	138,284			138,284
Other comprehensive income (loss)	1,141,817				1,141,817
Comprehensive income (loss)	1,280,101
Ending Balance at Mar. 31, 2019	6,997,027	0	5,554,059	1,726,917	(283,949)
Beginning Balance at Dec. 31, 2018	5,767,734	0	5,554,059	1,639,441	(1,425,766)
Increase (decrease) in shareowners' equity
Net income	347,021
Other comprehensive income (loss)	2,976,988
Comprehensive income (loss)	3,324,009
Ending Balance at Sep. 30, 2019	9,290,935	0	5,804,059	1,935,654	1,551,222
Beginning Balance at Mar. 31, 2019	6,997,027	0	5,554,059	1,726,917	(283,949)
Increase (decrease) in shareowners' equity
Net income	108,111			108,111
Other comprehensive income (loss)	1,007,798				1,007,798
Comprehensive income (loss)	1,115,909
Capital contributions from parent	250,000		250,000
Ending Balance at Jun. 30, 2019	8,362,936	0	5,804,059	1,835,028	723,849
Increase (decrease) in shareowners' equity
Net income	100,626			100,626
Other comprehensive income (loss)	827,373				827,373
Comprehensive income (loss)	927,999
Ending Balance at Sep. 30, 2019	$ 9,290,935	$ 0	$ 5,804,059	$ 1,935,654	$ 1,551,222