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Fair Value of Financial Instruments - Derivative Fair Value Measurements, Narrative (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Fair Value Disclosures [Abstract]
Total derivative assets valued with prices provided by models and other valuation techniques (as a percent)	9.00%
Total derivative liabilities valued with prices provided by models and other valuation techniques (as a percent)	4.00%
Increase in operating revenue	$ 14
Increase within cost of operations		$ 2

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- Definition

Credit Reserve Decrease, Increase in Operating Revenue

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- Definition

This element represents the portion of total fair value of all derivative assets, which are valued using various valuation techniques including internal models based on a fundamental analysis of the market and extrapolation of observable market data with similar characteristics.

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No definition available.

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- Definition

Derivative Liability, Fair Value Determined Using Valuation Techniques, Percentage

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No definition available.

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- Definition

Increase In Credit Reserve, Increase In Cost Of Revenue

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No definition available.

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