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Share-Based Payments (Tables)

12 Months Ended

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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Tabular disclosure of the number and weighted-average exercise prices (or conversion ratios) for stock awards granted to nonemployee directors that were outstanding at the beginning and end of the year, and the number of awards that were granted, exercised or converted, forfeited, and expired during the year.

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