Stock-Based Compensation (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	81.3
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	48.0
Performance Shares Units Converted into RTC, Carrier, or Otis RSUs	4.0
Share-based Payment Arrangement, Expense, Tax Benefit	$ 63	$ 47	$ 31
Proceeds from Stock Options Exercised	15	27	36
Share-based Payment Arrangement, Exercise of Option, Tax Benefit	48	75	59
Employee Service Share Based Compensation Tax Benefit Realized From Vesting Of Performance Share Units	58	36	13
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 315
Equity Awards Vested and Expected to Vest, Remaining Term	2 years 7 months 6 days
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Vested In Period Total Fair Value	$ 284	$ 211	$ 149
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Raytheon Company 2018 Stock Plan Shares Converted into Raytheon Technologies Shares	4.5
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 119.86
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Raytheon Company 2018 Stock Plan Shares Converted into Raytheon Technologies Shares	2.0
2018 LTIP Awards Converted into Carrier, Otis, and RTC Stock-Based Awards	5.5
Converted Awards Which Became Obligations of Carrier and Otis	7.1
Performance Share Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
2018 LTIP Awards Converted into Carrier, Otis, and RTC Stock-Based Awards	2.7
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 0	$ 117.87	$ 131.55
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Vested	$ 295	$ 188	$ 74
Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
2018 LTIP Awards Converted into Carrier, Otis, and RTC Stock-Based Awards	47.1
Converted Awards Which Became Obligations of Carrier and Otis	47.9
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 152.45
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
2018 LTIP Awards Converted into Carrier, Otis, and RTC Stock-Based Awards	1.7
Converted Awards Which Became Obligations of Carrier and Otis	1.4
Equity Awards Vested and Expected to Vest, Remaining Term	6 years 5 months 26 days
Stock Options/Stock Appreciation Rights SARS [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 23.37	$ 20.81	$ 20.24
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	$ 206	$ 383	$ 283

2018 LTIP Awards Converted into Carrier, Otis, and RTC Stock-Based Awards

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Disclosure of the aggregate tax benefit realized from the vesting of performance share units during the annual period.

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The total fair value of share-based awards for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares, other instruments, or cash in accordance with the terms of the arrangement.

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Intrinsic value of vested award under share-based payment arrangement. Excludes share and unit options.

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Weighted average remaining contractual term for fully vested and expected to vest exercisable or convertible options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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