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Share-Based Payments (Tables)

12 Months Ended

Dec. 31, 2017

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, 2017 by year of grant:

			As at December 31, 2017
			Restricted Share Units
RSU Holder			Amount Granted			Amount Vested			Amount Forfeited			Amount Outstanding
2015 Grants			287,852			173,755			38,886			75,211
2016 Grants			328,550			104,042			40,579			183,929
2017 Grants			200,021			—			19,585			180,436
Total												439,576

Summary of Restricted Share Unit Activity under 2013 Share Incentive Plan

A summary of RSUs under the Company’s 2013 Share Incentive Plan for the twelve months ended December 31, 2017, 2016 and 2015 is presented below:

			Twelve Months Ended
			December 31, 2017				December 31, 2016				December 31, 2015
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			530,340		$39.28		504,234		$40.45		519,112		$35.82
Granted			200,021		49.20		328,550		37.63		287,852		39.68
Vested			(245,704	)	39.63		(246,489	)	34.26		(266,944	)	34.26
Forfeited			(45,081	)	41.84		(55,955	)	39.51		(35,786	)	39.59
Outstanding restricted stock, end of period			439,576		$43.22		530,340		$39.28		504,234		$40.45

Summary of Performance and Phantom Shares by Grant Year

The following table summarizes information about phantom shares as at December 31, 2017 by year of grant:

		As at December 31, 2017
		Phantom Share Awards
		Amount Granted			Amount Vested			Amount Forfeited			Amount Outstanding
2015 Grants		135,651			52,720			82,931			—
2016 Grants		147,513			15,132			96,978			35,403
2017 Grants		173,619			—			90,342			83,277
Total											118,680

The following table summarizes information about performance shares as at December 31, 2017 by year of grant:

		As at December 31, 2017
		Performance Share Awards
		Amount Granted			Amount Vested			Amount Forfeited			Amount Outstanding
2015 Grants		277,585			107,882			169,703			—
2016 Grants		278,477			28,566			168,224			81,687
2017 Grants		216,878			—			89,643			127,235
Total											208,922

Summary of Performance and Phantom Share Activity under 2013 Share Incentive Plan

A summary of performance share activity under the Company’s 2013 Share Incentive Plan for the twelve months ended December 31, 2017, 2016 and 2015 is presented below:

			Twelve Months Ended
			December 31, 2017					December 31, 2016				December 31, 2015
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			254,988		$36.92			266,424		$24.17		268,418		$25.35
Granted			216,878		47.30			278,477		34.44		277,585		38.92
Vested			—		—			(87,059	)	37.30		(208,830	)	38.11
Forfeited			(262,944	)	40.32			(202,854	)	36.93		(70,749	)	30.26
Outstanding performance shares, end of period			208,922		$38.71			254,988		$36.92		266,424		$24.17

A summary of phantom share activity under the Company’s 2013 Share Incentive Plan for the twelve months ended December 31, 2017, 2016 and 2015 is presented below:

			Twelve Months Ended
			December 31, 2017					December 31, 2016				December 31, 2015
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			131,464		$35.90			130,319		$38.75		143,248		$35.32
Granted			173,619		47.30			147,513		34.44		135,651		38.92
Vested			—		—			(36,159	)	36.96		(151,668	)	34.98
Forfeited			(186,403	)	40.32			(110,209	)	36.96		3,087		35.65
Outstanding performance shares, end of period			118,680		$38.71			131,464		$35.90		130,319		$38.75

Summary of Vesting Criteria

A summary of the increases in adjusted BVPS is presented below:

Year ended December 31,		Increase in BVPS
2013		6.2	%
2014		13.3	%
2015		10.7	%
2016		5.9	%
2017		—	%

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, 2017.

		As at December 31, 2017
		Restricted Share Units
		Amount Granted			Amount Vested			Amount Forfeited			Amount Outstanding
Non-Employee Directors
2015		27,620			27,620			—			—
2016		24,456			21,352			3,104			—
2017		22,230			17,043			1,853			3,334
Chairman
2015		12,154			12,154			—			—
2016		10,952			10,952			—			—
2017		8,892			7,410			—			1,482
Total		106,304			96,531			4,957			4,816

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, 2017, 2016 and 2015 is presented below:

			Twelve Months Ended
			December 31, 2017				December 31, 2016				December 31, 2015
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			5,171		$41.07		6,636		$45.28		6,806		$35.83
Granted			31,122		50.18		35,408		41.07		39,774		45.25
Vested			(29,624	)	48.59		(33,769	)	41.89		(39,944	)	43.81
Forfeited			(1,853	)	50.18		(3,104	)	41.07		—		0.00
Outstanding restricted stock, end of period			4,816		$50.19		5,171		$41.07		6,636		$45.28

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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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-Publisher FASB
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Tabular disclosure for stock option plans. Includes, but is not limited to, outstanding awards at beginning and end of year, grants, exercises, forfeitures, and weighted-average grant date fair value.

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Tabular disclosure of the number and weighted-average grant date fair value for outstanding performance shares.

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