Financial Guarantee Insurance Contracts Financial Guarantee Insurance Contracts - Insurance Intangible Asset Details (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Intangible Assets, Gross (Excluding Goodwill)	$ 1,260		$ 1,260		$ 1,273
Finite-Lived Intangible Assets, Accumulated Amortization	868		868		847
Insurance intangible asset	392		392		$ 427
Amortization of insurance intangible assets	$ 14	$ 226	$ 27	$ 263

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount before accumulated amortization of intangible assets, excluding goodwill.

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No definition available.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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