| Stockholders' Equity - Stock Repurchase Program (Details) shares in Millions | Mar. 31, 2019  USD ($)  shares | 
|---|---|
| Class of Stock [Line Items] | |
| Number of shares repurchased (in shares) | shares | 2,784 | 
| Aggregate cost for shares repurchased | $ 11,278,000,000 | 
| Remaining amount authorized under the stock repurchase program | 2,722,000,000 | 
| Common Stock | |
| Class of Stock [Line Items] | |
| Stock repurchase program, aggregate authorized amount | $ 14,000,000,000 | 
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- Definition Share repurchase program, shares repurchased cost. No definition available. 
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- Definition Stock repurchase program, number of shares repurchased. No definition available. 
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available. 
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- Definition Amount of stock repurchase plan authorized. No definition available. 
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- Definition Amount remaining of a stock repurchase plan authorized. No definition available. 
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- Details 
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