Consolidated Balance Sheets - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Successor [Member]
Current assets:
Cash and cash equivalents	$ 993
Accounts receivable, less allowances of $18 and $130, respectively	504
Prepaid expenses	111
Income taxes and other current assets	17
Total current assets	1,625
Property, plant and equipment, net	8,686
Other intangibles, net	4,389
Other assets	402
Total assets	15,102
Current liabilities:
Long-term debt due within one year	15
Accounts payable	561
Advanced billings	205
Accrued other taxes	195
Accrued interest	63
Pension and other postretirement benefits	48
Other current liabilities	304
Total current liabilities	1,391
Deferred income taxes	342
Pension and other postretirement benefits	1,684
Other liabilities	430
Long-term debt	7,007
Total liabilities not subject to compromise	10,854
Total liabilities	10,854
Equity (Deficit):
Common stock	2
Additional paid-in capital	4,106
Retained earnings (deficit)	99
Accumulated other comprehensive income (loss), net of tax	41
Total equity (deficit)	4,248
Total liabilities and equity (deficit)	$ 15,102
Predecessor [Member]
Current assets:
Cash and cash equivalents		$ 1,829
Accounts receivable, less allowances of $18 and $130, respectively		553
Contract acquisition costs		97
Prepaid expenses		90
Income taxes and other current assets		85
Total current assets		2,654
Property, plant and equipment, net		12,931
Other intangibles, net		677
Other assets		533
Total assets		16,795
Current liabilities:
Long-term debt due within one year		5,781
Accounts payable		540
Advanced billings		202
Accrued other taxes		204
Accrued interest		47
Pension and other postretirement benefits		48
Other current liabilities		318
Total current liabilities		7,140
Deferred income taxes		343
Pension and other postretirement benefits		2,195
Other liabilities		452
Total liabilities not subject to compromise		10,130
Liabilities subject to compromise		11,565
Total liabilities		21,695
Equity (Deficit):
Common stock		27
Additional paid-in capital		4,817
Retained earnings (deficit)		(8,975)
Accumulated other comprehensive income (loss), net of tax		(755)
Treasury common stock		(14)
Total equity (deficit)		(4,900)
Total liabilities and equity (deficit)		$ 16,795