Stock-Based Compensation (Tables)

As of September 30, 2015, the unrecognized compensation cost and remaining weighted-average amortization related to stock-based awards were as follows:

							Performance-
							based
					Restricted		Restricted
		Stock	Restricted		Stock		Stock
(in thousands)		Options	Shares		Units		Units⁽¹⁾
Unrecognized compensation cost	$	4,823	$	239	$	7,853	$	2,795
Remaining weighted-average
amortization period	1.8 years		0.4 years		2.4 years		2.1 years

⁽¹⁾ Based on the probable achievement of the performance goals identified in each award.

The weighted-average assumptions used to value the options granted during the three and nine months ended September 30, 2015 and 2014, were as follows:

	Three Months Ended		Nine Months Ended
	September 30,		September 30,
(in thousands)	2015	2014	2015	2014
Options granted	-	-	289	378
Expected term of options	N/A	N/A	6.4 years	7.0 years
Expected volatility	N/A	N/A	35%	39%
Risk-free interest rate	N/A	N/A	1.886%	2.081%
Dividend yield	N/A	N/A	zero	zero

The following table summarizes activities relating to the Company’s stock options:


				Weighted-
			Weighted-	Average
			Average	Remaining		Aggregate
	Number of		Exercise	Contractual		Intrinsic
(in thousands, except per share data)	Options		Price	Term (Years)		Value
Outstanding as of December 31, 2014	2,437	$	20.07
Granted	289	$	23.14
Exercised	(94)	$	17.89
Forfeited or expired	(21)	$	22.91
Outstanding as of September 30, 2015	2,611	$	20.47	4.88	$	6,498
Exercisable as of September 30, 2015	1,832	$	20.16	3.05	$	5,353

The following table summarizes activities related to the Company’s restricted shares:

			Weighted-
			Average
	Number of		Grant Date
(in thousands, except per share data)	Shares		Fair Value
Non-vested shares outstanding as of December 31, 2014	109	$	16.33
Vested	(70)	$	16.84
Forfeited	(1)	$	16.57
Non-vested shares outstanding as of September 30, 2015	38	$	15.38

The following table summarizes the activities related to the Company’s time-based restricted stock units:

			Weighted-
			Average
	Number of		Grant Date
(in thousands, except per share data)	Units		Fair Value
Non-vested awards outstanding as of December 31, 2014	412	$	20.33
Granted	210	$	23.22
Vested	(151)	$	20.29
Forfeited	(9)	$	21.24
Non-vested awards outstanding as of September 30, 2015	462	$	21.64

The following table summarizes the activities related to the Company’s performance-based restricted stock units:

			Weighted-
			Average
	Number of		Grant Date
(in thousands, except per share data)	Units		Fair Value
Non-vested units outstanding as of December 31, 2014	274	$	18.56
Granted⁽¹⁾	85	$	22.93
Forfeited or expired	(53)	$	18.57
Non-vested units outstanding as of September 30, 2015	306	$	19.77

⁽¹⁾Represents target number of units that can vest based on the achievement of the performance goals.