Consolidated Balance Sheets (Parenthetical) - $ / shares |
Dec. 31, 2019 |
Dec. 31, 2018 |
|---|---|---|
| Statement Of Financial Position [Abstract] | ||
| Common shares, par value | $ 0.0005 | $ 0.0005 |
| Common shares, shares authorized | 2,000,000,000.0 | 2,000,000,000.0 |
| Common shares, shares outstanding | 137,400,000 | 142,800,000 |
| Treasury stock shares, at cost | 10,000,000.0 | 10,000,000.0 |
| X | ||||||||||
- Definition Face amount or stated value per share of common stock. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition The maximum number of common shares permitted to be issued by an entity's charter and bylaws. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Number of previously issued common shares repurchased by the issuing entity and held in treasury. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|