Stockholders' Equity - Shares of Common Stock Issued Under Employee Stock Purchase Plan (Details) - $ / shares |
12 Months Ended | ||
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Dec. 31, 2020 |
Dec. 31, 2019 |
Dec. 31, 2018 |
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| Increase (Decrease) in Stockholders' Equity [Roll Forward] | |||
| Number of shares available, beginning balance (in shares) | 171,069 | ||
| Shares issued during period (in shares) | 14,313 | 19,895 | 18,725 |
| Number of shares available, ending balance (in shares) | 118,136 | ||
| Weighted average per share price of shares issued (in dollars per share) | $ 152.10 | $ 103.84 | $ 71.12 |
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- Definition Weighted average per share price for shares issued during the period as a result of the employee stock purchase plan. No definition available.
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- Definition Shares available under employee stock purchase plan. No definition available.
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition Number of shares issued during the period as a result of an employee stock purchase plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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