XML 37 R34.htm IDEA: XBRL DOCUMENT v3.19.3.a.u2
SHARE-BASED PAYMENTS (Tables)
 12 Months Ended
Dec. 31, 2019
Share-based Payments [Line Items]  
Schedule of Share-based Compensation, Restricted Stock Units Activity The following tables set forth activity and various statistics for restricted stock unit awards outstanding under the respective plans for the period indicated:
 
 
Number of
Units
 
Weighted-
Average Price
Nonvested at December 31, 2018
 
109,506

 
$
63.45

Granted
 
35,753

 
$
83.94

Vested
 
(39,418
)
 
$
58.60

Forfeited
 
(1,443
)
 
$
69.87

Nonvested at December 31, 2019
 
104,398

 
$
72.21

 
 
2019
 
2018
 
2017
Weighted-average grant date fair value (per share)
 
$
83.94

 
$
68.17

 
$
63.97

Fair value of shares granted (thousands of dollars)
 
$
3,001

 
$
2,583

 
$
2,420
Schedule of Nonvested Performance-based Units Activity The following tables set forth activity and various statistics related to our performance stock unit awards and the assumptions used by us in the valuations of the 2019, 2018 and 2017 grants at the grant date:
 
 
Number of
Units
 
Weighted-
Average Price
Nonvested at December 31, 2018
 
219,331

 
$
69.21

Granted
 
71,237

 
$
89.86

Vested
 
(70,548
)
 
$
64.06

Forfeited
 
(1,844
)
 
$
73.57

Nonvested at December 31, 2019
 
218,176

 
$
77.58

 
 
2019
 
2018
 
2017
 
Volatility (a)
 
18.70%
 
18.80%
 
20.70%
 
Dividend yield
 
2.38%
 
2.70%
 
2.63%
 
Risk-free interest rate (b)
 
2.50%
 
2.38%
 
1.48%
 
(a) - Volatility based on historical volatility over three years using daily stock price observations of our peer utilities.
(b) - Using 3-year treasury.
 
 
2019
 
2018
 
2017
Weighted-average grant date fair value (per share)
 
$
89.86

 
$
74.04

 
$
68.94

Fair value of shares granted (thousands of dollars)
 
$
6,401

 
$
5,882

 
$
5,110