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Share-Based Payments (Tables) | 12 Months Ended
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Dec. 31, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract] |
Summary of Restricted Share Units by Grant Year | The following table summarizes information about RSUs as at December 31, 2018 by year of grant:
|  |  | As at December 31, 2018
|  |  | Restricted Share Units
RSU Holder |  |  | Amount Granted |  | Amount Vested |  | Amount Forfeited |  | Amount Outstanding
2016 Grants |  | 328,550 |  |  | 186,862 |  |  | 82,728 |  |  | 58,960 |
2017 Grants |  | 200,021 |  |  | 62,433 |  |  | 37,035 |  |  | 100,553 |
2018 Grants |  | 228,251 |  |  | — |  |  | 25,192 |  |  | 203,059 |
Total |  |  |  |  |  |  |  | 362,572 |
Summary of Restricted Share Unit Activity under 2013 Share Incentive Plan | A summary of RSU activity for the twelve months ended December 31, 2018, 2017 and 2016 is presented below:
|  |  | Twelve Months Ended
|  |  | December 31, 2018 |  | December 31, 2017 |  | December 31, 2016
Restricted share unit activity |  |  | Number of Shares | Weighted Average Grant Date FV |  | Number of Shares | Weighted Average Grant Date FV |  | Number of Shares | Weighted Average Grant Date FV
Outstanding restricted stock, beginning of period |  | 439,576 |  | $43.22 |  | 530,340 |  | $39.28 |  | 504,234 |  | $40.45
Granted |  | 228,251 |  | 33.22 |  | 200,021 |  | 49.20 |  | 328,550 |  | 37.63
Vested |  | (222,669 | ) | 39.67 |  | (245,704 | ) | 39.63 |  | (246,489 | ) | 34.26
Forfeited |  | (82,586 | ) | 40.04 |  | (45,081 | ) | 41.84 |  | (55,955 | ) | 39.51
Outstanding restricted stock, end of period |  | 362,572 |  | $38.29 |  | 439,576 |  | $43.22 |  | 530,340 |  | $39.28
Summary of Performance and Phantom Shares by Grant Year | The following table summarizes information about phantom shares as at December 31, 2018 by year of grant:
|  | As at December 31, 2018
|  | Phantom Share Awards
|  | Amount Granted |  | Amount Vested |  | Amount Forfeited |  | Amount Outstanding
2016 Grants |  | 147,513 |  |  | 15,132 |  |  | 132,381 |  |  | — |
2017 Grants |  | 173,619 |  |  | — |  |  | 131,980 |  |  | 41,639 |
2018 Grants |  | 150,185 |  |  | — |  |  | 78,097 |  |  | 72,088 |
Total |  |  |  |  |  |  |  | 113,727 |
The following table summarizes information about performance shares as at December 31, 2018 by year of grant:
|  | As at December 31, 2018
|  | Performance Share Awards
|  | Amount Granted |  | Amount Vested |  | Amount Forfeited |  | Amount Outstanding
2016 Grants |  | 278,477 |  |  | 28,566 |  |  | 249,911 |  |  | — |
2017 Grants |  | 216,878 |  |  | — |  |  | 163,114 |  |  | 53,764 |
2018 Grants |  | 215,273 |  |  | — |  |  | 90,371 |  |  | 124,902 |
Total |  |  |  |  |  |  |  | 178,666 |
Summary of Performance and Phantom Share Activity under 2013 Share Incentive Plan | A summary of performance share activity for the twelve months ended December 31, 2018, 2017 and 2016 is presented below:
|  |  | Twelve Months Ended
|  |  | December 31, 2018 |  | December 31, 2017 |  | December 31, 2016
Performance Share Activity |  |  | Number of Shares | Weighted Average Grant Date FV |  | Number of Shares | Weighted Average Grant Date FV |  | Number of Shares | Weighted Average Grant Date FV
Outstanding performance shares, beginning of period |  | 208,922 |  | $38.71 |  | 254,988 |  | $36.92 |  | 266,424 |  | $24.17
Granted |  | 215,273 |  | 30.20 |  | 216,878 |  | 47.30 |  | 278,477 |  | 34.44
Vested |  | — |  | — |  |  | — |  | — |  |  | (87,059 | ) | 37.30
Forfeited |  | (245,529 | ) | 36.73 |  | (262,944 | ) | 40.32 |  | (202,854 | ) | 36.93
Outstanding performance shares, end of period |  | 178,666 |  | $38.71 |  | 208,922 |  | $38.71 |  | 254,988 |  | $36.92
A summary of phantom share activity for the twelve months ended December 31, 2018, 2017 and 2016 is presented below:
|  |  | Twelve Months Ended
|  |  | December 31, 2018 |  | December 31, 2017 |  | December 31, 2016
Phantom Share Activity |  |  | Number of Shares | Weighted Average Grant Date FV |  | Number of Shares | Weighted Average Grant Date FV |  | Number of Shares | Weighted Average Grant Date FV
Outstanding performance shares, beginning of period |  | 118,680 |  | $38.71 |  | 131,464 |  | $35.90 |  | 130,319 |  | $38.75
Granted |  | 150,185 |  | 30.20 |  | 173,619 |  | 47.30 |  | 147,513 |  | 34.44
Vested |  | — |  | — |  |  | — |  | — |  |  | (36,159 | ) | 36.96
Forfeited |  | (155,138 | ) | 35.76 |  | (186,403 | ) | 40.32 |  | (110,209 | ) | 36.96
Outstanding performance shares, end of period |  | 113,727 |  | $36.46 |  | 118,680 |  | $38.71 |  | 131,464 |  | $35.90
Summary of Vesting Criteria | A summary of the increases in adjusted BVPS is presented below:
Year ended December 31, |  | Increase in BVPS
2014 |  | 13.3 | %
2015 |  | 10.7 | %
2016 |  | 5.9 | %
2017 |  | — | %
2018 |  | — | %
Fair Value of Employee Options Granted under ESPP | The fair value of the employee options granted under the ESPP was estimated on the date of grant using a modified Black-Scholes option pricing model under the following assumptions:
Grant Date |  | Per share weighted average fair value |  | Risk free interest rate |  | Dividend yield |  | Expected life |  | Share price volatility
|  | ($) |  | (%) |  | (%) |  | (in years) |  | (%)
March 25, 2015 |  | 8.17 |  | 0.94 |  |  | 1.78 |  |  | 3 |  | 16.00 |
March 25, 2015 |  | 7.08 |  | 0.60 |  |  | 1.78 |  |  | 2 |  | 16.00 |
March 25, 2016 |  | 7.97 |  | 1.04 |  |  | 1.88 |  |  | 3 |  | 4.21 |
March 25, 2016 |  | 7.00 |  | 0.87 |  |  | 1.88 |  |  | 2 |  | 2.44 |
April 28, 2017 |  | 6.69 |  | 1.44 |  |  | 1.83 |  |  | 3 |  | 3.67 |
April 28, 2017 |  | 8.70 |  | 1.44 |  |  | 1.83 |  |  | 3 |  | 3.67 |
April 28, 2017 |  | 8.70 |  | 1.26 |  |  | 1.83 |  |  | 2 |  | 3.52 |
Summary of Non-Employee Director Restricted Share Units by Grant Year | The following table summarizes information about RSUs issued to non-employee directors by year of grant as at December 31, 2018.
|  | As at December 31, 2018
|  | Restricted Share Units
|  | Amount Granted |  | Amount Vested |  | Amount Forfeited |  | Amount Outstanding
Non-Employee Directors |  |  |  |  |  |  |  |
2016 |  | 24,456 |  |  | 21,352 |  |  | 3,104 |  |  | — |
2017 |  | 22,230 |  |  | 20,377 |  |  | 1,853 |  |  | — |
2018 |  | 29,025 |  |  | 24,187 |  |  | — |  |  | 4,838 |
Chairman |  |  |  |  |  |  |  |
2016 |  | 10,952 |  |  | 10,952 |  |  | — |  |  | — |
2017 |  | 8,892 |  |  | 8,892 |  |  | — |  |  | — |
2018 |  | 12,900 |  |  | 10,750 |  |  | — |  |  | 2,150 |
Total |  | 108,455 |  |  | 96,510 |  |  | 4,957 |  |  | 6,988 |
Summary of Restricted Share Unit, Non Employee Directors, under 2013 Share Incentive Plan | A summary of RSU activity relating to non-employee directors under the Company’s 2013 Share Incentive Plan for the twelve months ended December 31, 2018, 2017 and 2016 is presented below:
|  |  | Twelve Months Ended
|  |  | December 31, 2018 |  | December 31, 2017 |  | December 31, 2016
Restricted share unit activity |  |  | Number of Shares | Weighted Average Grant Date FV |  | Number of Shares | Weighted Average Grant Date FV |  | Number of Shares | Weighted Average Grant Date FV
Outstanding restricted stock, beginning of period |  | 4,816 |  | $50.19 |  | 5,171 |  | $41.07 |  | 6,636 |  | $45.28
Granted |  | 41,925 |  | 33.08 |  | 31,122 |  | 50.18 |  | 35,408 |  | 41.07
Vested |  | (39,753 | ) | 35.15 |  | (29,624 | ) | 48.59 |  | (33,769 | ) | 41.89
Forfeited |  | — |  | 0.00 |  | (1,853 | ) | 50.18 |  | (3,104 | ) | 41.07
Outstanding restricted stock, end of period |  | 6,988 |  | $33.08 |  | 4,816 |  | $50.19 |  | 5,171 |  | $41.07

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