Statements of Equity - USD ($) $ in Thousands	Total	Transferred To From Affiliates	Common Stock	Additional  Paid-in Capital	Additional  Paid-in Capital Transferred To From Affiliates	Retained (Deficit) Earnings	Accumulated Other Comprehensive Income (Loss)	Parent
Beginning balance at Dec. 31, 2020			$ 3,000	$ 4,383,000		$ (3,217,000)	$ 1,533,000	$ 2,702,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Return of capital				(3,813,000)				(3,813,000)
Dividend to parent	$ (831,000)					(831,000)
Assets purchased/transferred from/to affiliates		$ 22,000			$ 22,000
Comprehensive loss:
Net income (loss)	4,965,000					4,965,000		4,965,000
Other comprehensive loss, net of tax	(1,363,000)						(1,363,000)	(1,363,000)
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest, Total								3,602,000
Ending balance at Dec. 31, 2021			3,000	592,000		917,000	170,000	1,682,000
Comprehensive loss:
Net income (loss)	356,000
Other comprehensive loss, net of tax	(443,000)
Ending balance at Mar. 31, 2022			3,000	286,000		1,273,000	(273,000)	1,289,000
Comprehensive loss:
Net income (loss)	(286,000)
Other comprehensive loss, net of tax	111,000
Ending balance at Dec. 31, 2022			3,000	1,759,000		(286,000)	111,000	1,587,000
Beginning balance at Apr. 01, 2022			3,000	1,759,000		0	0	1,762,000
Comprehensive loss:
Net income (loss)						(286,000)		(286,000)
Other comprehensive loss, net of tax							111,000	111,000
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest, Total								(175,000)
Ending balance at Dec. 31, 2022			3,000	1,759,000		(286,000)	111,000	1,587,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Distribution to parent	(45,000)			(45,000)
Comprehensive loss:
Net income (loss)	(4,000)					(4,000)		(4,000)
Other comprehensive loss, net of tax	$ (176,000)						(176,000)	(176,000)
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest, Total								(180,000)
Ending balance at Dec. 31, 2023			$ 3,000	$ 1,714,000		$ (290,000)	$ (65,000)	$ 1,362,000