Share capital

9 Months Ended

Sep. 30, 2016

Equity [Abstract]

Share capital

The following tables are a summary of the common shares issued and outstanding and shares repurchased held as treasury shares as of and for the nine months ended September 30, 2016 and 2015:

Common shares	2016	2015
Balance, beginning of period	105,479,341	104,473,402
Options exercised	388,152	433,279
Restricted shares granted	47,712	110,853
Performance restricted shares granted, net of forfeitures	468,723	461,807
Balance, end of period	106,383,928	105,479,341

Treasury shares	2016	2015
Balance, beginning of period	—	—
Repurchase of common shares	644,768	—
Balance, end of period	644,768	—

Authorized and issued

The Company’s authorized share capital of $33.0 million is comprised of 300,000,000 common shares with a par value of $0.10 each and 30,000,000 preference shares with a par value of $0.10 each. No preference shares have been issued to date.

Share repurchases

On May 4, 2016, the Company’s Board of Directors authorized a common share repurchase program for up to an aggregate of $100.0 million of the Company’s outstanding common shares. Under the common share repurchase program, the Company may repurchase shares from time to time in privately negotiated transactions or in open-market purchases in accordance with all applicable securities laws and regulations, including Rule 10b-18 of the Securities Exchange Act of 1934, as amended.

During the three months ended September 30, 2016, the Company did not repurchase any of its common shares.

During the nine months ended September 30, 2016, the Company repurchased 644,768 of its common shares in the open market for an aggregate cost of $7.4 million at a weighted average cost, including commissions, of $11.46 per share. Common shares repurchased by the Company were not canceled and are classified as treasury shares.

As of September 30, 2016, the Company may repurchase up to an aggregate of $92.6 million of additional common shares under its share repurchase program.