13. Share-Based Payment Arrangements

The Company maintains incentive compensation plans that provide for awards of share-based compensation to employees and directors. These plans have been approved by the Company’s shareholders. Detailed descriptions of these plans were included in Note 17 to the consolidated financial statements in the Company’s Annual Report on Form 10-K for the year ended December 31, 2017.

A summary of stock option activity for the six months ended June 30, 2018 is presented below:



				Weighted
				Average
		Weighted		Remaining
		Average		Contractual	Aggregate
	Number of	Exercise		Term	Intrinsic
Options	Shares	Price		(Years)	Value ($000)
Outstanding at January 1, 2018	88,301	$	34.84	2.8	$	1,294
Exercised/Released	(32,458)		37.02			564
Cancelled/Forfeited	—		—			—
Expired	(2,298)		44.91			10
Outstanding at June 30, 2018	53,545	$	33.09	2.8	$	726
Exercisable at June 30, 2018	53,545	$	33.09	2.8	$	726

The total intrinsic value of options exercised for the six months ended June 30, 2018 and 2017 was $0.6 million and $4.1 million, respectively.

The Company’s restricted and performance-based share awards to certain employees and directors are subject to service requirements. A summary of the status of the Company’s nonvested restricted and performance-based share awards as of June 30, 2018 and changes during the six months ended June 30, 2018, is presented in the following table.



			Weighted
			Average
	Number of		Grant Date
	Shares		Fair Value
Nonvested at January 1, 2018	1,708,942	$	37.05
Granted	82,876		48.81
Vested	(28,835)		32.65
Forfeited	(49,687)		36.49
Nonvested at June 30, 2018	1,713,296	$	37.60

As of June 30, 2018, there was $43.5 million of total unrecognized compensation expense related to nonvested restricted and performance shares expected to vest. This compensation is expected to be recognized in expense over a weighted average period of 3.2 years. The total fair value of shares which vested during the six months ended June 30, 2018 and 2017 was $0.9 million and $10.0 million, respectively.

During the six months ended June 30, 2018, the Company granted 26,147 performance share awards subject to a total shareholder return (“TSR”) performance metric with a grant date fair value of $51.13 per share and 26,147 performance shares subject to an operating earnings per share performance metric with a grant date fair value of $44.84 per share to key members of executive management. The number of performance shares subject to TSR that ultimately vest at the end of the three-year performance period, if any, will be based on the relative rank of the Company’s three-year TSR among the TSRs of a peer group of 43 regional banks. The fair value of the performance shares subject to TSR at the grant date was determined using a Monte Carlo simulation method. The number of performance shares subject to core earnings per share that ultimately vest will be based on the Company’s attainment of certain core earnings per share goals over the two-year performance period. The maximum number of performance shares that could vest is 200% of the target award. Compensation expense for these performance shares is recognized on a straight line basis over the three-year service period.