Stockholders' Equity - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions |
1 Months Ended | 6 Months Ended | |
|---|---|---|---|
May 31, 2017 |
Jun. 30, 2017 |
Jun. 30, 2016 |
|
| Equity [Abstract] | |||
| Shares of common stock, authorized (shares) | 600,000,000 | ||
| Shares of common stock, issued and sold (shares) | 170,712,093 | ||
| Stock issued during period, shares, new issues | 3,822,126 | 3,710,925 | |
| Stock repurchased and retired during period (shares) | 540,806 | 0 | |
| Stock repurchased and retired during period, value | $ 55.0 | ||
| Stock repurchased and retired during period (in USD per share) | $ 101.70 | ||
| X | ||||||||||
- Definition Stock Repurchased And Retired During Period, Value Per Share No definition available.
|
| X | ||||||||||
- Definition The maximum number of common shares permitted to be issued by an entity's charter and bylaws. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Number of new stock issued during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Number of shares that have been repurchased and retired during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital). Reference 1: http://www.xbrl.org/2003/role/presentationRef
|