CONDENSED CONSOLIDATED STATEMENTS OF INCOME (LOSS) (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Revenues
Net sales and operating revenues	$ 4,731	$ 3,836
Costs and expenses
Cost of sales (exclusive of depreciation and amortization)	4,061	3,339
Selling, general, and administrative	255	249
Depreciation and amortization	155	171
Engineering, research, and development	72	77
Restructuring charges, net and asset impairments	25	484
Goodwill and intangible impairment charges	0	383
Costs and expenses	4,568	4,703
Other income (expense)
Non-service pension and postretirement benefit (costs) credits	3	1
Equity in earnings (losses) of nonconsolidated affiliates, net of tax	22	13
Gain (loss) on extinguishment of debt	8	0
Other income (expense), net	8	8
Total other expense (income)	41	22
Earnings (loss) before interest expense, income taxes, and noncontrolling interests	204	(845)
Interest expense	(70)	(75)
Earnings (loss) before income taxes and noncontrolling interests	134	(920)
Income tax (expense) benefit	(47)	94
Net income (loss)	87	(826)
Less: Net income (loss) attributable to noncontrolling interests	22	13
Net income (loss) attributable to Tenneco Inc.	$ 65	$ (839)
Basic earnings (loss) per share:
Earnings (loss) per share (in dollars per share)	$ 0.80	$ (10.34)
Weighted average shares outstanding (in shares)	81,953,133	81,168,562
Diluted earnings (loss) per share:
Earnings (loss) per share (in dollars per share)	$ 0.79	$ (10.34)
Weighted average shares outstanding (in shares)	82,524,129	81,168,562