Common Stock (Tables)

9 Months Ended

Sep. 30, 2017

Equity [Abstract]

Schedule of reconciliation of changes in common shares issued

A reconciliation of changes in common shares issued during the nine months ended September 30, 2017 is as follows:

Shares issued at December 31, 2016	59,684,669
Issued as restricted stock award grants	273,829
Issued upon exercise of stock options	663,288
Shares issued at September 30, 2017	60,621,786