SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019	Jun. 30, 2018
Retained earnings	$ 2,987	$ 2,922
Accounting Standards Update 2018-02 [Member]
Retained earnings			$ 254

The cumulative amount of the reporting entity's undistributed earnings or deficit.

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