Stockholder's Equity - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Stockholder's Equity (Deficit)
Common stock, share issued (shares)	1	1
Common stock, share outstanding (shares)	1	1
Dividends
Cash dividend declared to QSC	$ 1,725	$ 1,600	$ 1,275
Cash dividend paid to QSC	$ 1,725	$ 1,600	$ 1,275
COMMON STOCK
Stockholder's Equity (Deficit)
Common stock, share issued (shares)	1
Common stock, share outstanding (shares)	1

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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-Publisher FASB
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-SubTopic 10
-Section S99
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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.

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Cash outflow in the form of capital distributions and dividends to common shareholders, preferred shareholders and noncontrolling interests.

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