| December 31, 2017 | December 31, 2016 | January 1, 2016 | |||||||||||||||||||||||
| Authorized | Issued and outstanding | Authorized | Issued and outstanding | Authorized | Issued and outstanding | ||||||||||||||||||||
| Number of shares | |||||||||||||||||||||||||
| Ordinary shares of NIS 1 par value each | 500,000,000 | (*193,510,391 | 500,000,000 | (*196,563,321 | 500,000,000 | (*196,509,883 | |||||||||||||||||||
| *) | As of December 31, 2017 of which NIS 51,500 par value of shares held in treasury by the Company and as at December 31, 2016 and January 1, 2016 of which NIS 1,046,993 par value shares are held in treasury by the Company. |