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Benefit Plans
6 Months Ended
Jun. 30, 2016
Benefit Plans
BENEFIT PLANS
NOTE 9(a) Pension and Other Postretirement Benefits Plans -
Net Periodic Benefit Costs (Credits) - The components of net periodic benefit costs (credits) for sponsored defined benefit pension and OPEB plans for the three and six months ended June 30 are included in the tables below (in millions). In IPL’s and WPL’s tables below, the defined benefit pension plans costs represent those respective costs for their bargaining unit employees covered under the qualified plans that they sponsor, as well as amounts directly assigned to them related to their current and former non-bargaining employees who are participants in the Alliant Energy and Corporate Services sponsored qualified and non-qualified defined benefit pension plans. In IPL’s and WPL’s tables below, the OPEB plans costs (credits) represent respective costs (credits) for their employees, as well as amounts directly assigned to them related to their current and former non-bargaining employees who are participants in the Corporate Services sponsored OPEB plan.
 
Defined Benefit Pension Plans
 
OPEB Plans
 
Three Months
 
Six Months
 
Three Months
 
Six Months
Alliant Energy
2016
 
2015
 
2016
 
2015
 
2016
 
2015
 
2016
 
2015
Service cost

$3.1

 

$3.9

 

$6.3

 

$7.9

 

$1.3

 

$1.4

 

$2.6

 

$2.8

Interest cost
13.2

 
13.4

 
26.5

 
26.8

 
2.4

 
2.3

 
4.7

 
4.5

Expected return on plan assets
(16.4
)
 
(18.8
)
 
(32.8
)
 
(37.5
)
 
(1.5
)
 
(2.1
)
 
(3.0
)
 
(4.2
)
Amortization of prior service credit

 

 
(0.1
)
 
(0.1
)
 
(1.1
)
 
(2.8
)
 
(2.1
)
 
(5.6
)
Amortization of actuarial loss
9.4

 
8.9

 
18.7

 
17.7

 
1.2

 
1.2

 
2.4

 
2.4

Additional benefit costs

 
0.1

 

 
0.3

 

 

 

 

 

$9.3

 

$7.5

 

$18.6

 

$15.1

 

$2.3

 

$—

 

$4.6

 

($0.1
)
 
Defined Benefit Pension Plans
 
OPEB Plans
 
Three Months
 
Six Months
 
Three Months
 
Six Months
IPL
2016
 
2015
 
2016
 
2015
 
2016
 
2015
 
2016
 
2015
Service cost

$1.9

 

$2.2

 

$3.8

 

$4.4

 

$0.6

 

$0.6

 

$1.2

 

$1.2

Interest cost
6.2

 
6.3

 
12.3

 
12.5

 
0.9

 
1.0

 
1.9

 
1.9

Expected return on plan assets
(7.8
)
 
(9.0
)
 
(15.5
)
 
(17.9
)
 
(1.2
)
 
(1.4
)
 
(2.2
)
 
(2.8
)
Amortization of prior service credit
(0.1
)
 
(0.1
)
 
(0.1
)
 
(0.1
)
 
(0.6
)
 
(1.6
)
 
(1.3
)
 
(3.1
)
Amortization of actuarial loss
4.1

 
3.9

 
8.2

 
7.7

 
0.7

 
0.5

 
1.3

 
1.1

 

$4.3

 

$3.3

 

$8.7

 

$6.6

 

$0.4

 

($0.9
)
 

$0.9

 

($1.7
)
 
Defined Benefit Pension Plans
 
OPEB Plans
 
Three Months
 
Six Months
 
Three Months
 
Six Months
WPL
2016
 
2015
 
2016
 
2015
 
2016
 
2015
 
2016
 
2015
Service cost

$1.2

 

$1.5

 

$2.4

 

$2.9

 

$0.5

 

$0.5

 

$1.0

 

$1.1

Interest cost
5.6

 
5.7

 
11.2

 
11.3

 
1.0

 
0.9

 
1.9

 
1.8

Expected return on plan assets
(7.1
)
 
(8.1
)
 
(14.2
)
 
(16.2
)
 
(0.2
)
 
(0.4
)
 
(0.4
)
 
(0.8
)
Amortization of prior service cost (credit)

 

 
0.1

 
0.1

 
(0.2
)
 
(0.8
)
 
(0.4
)
 
(1.7
)
Amortization of actuarial loss
4.4

 
4.2

 
8.8

 
8.4

 
0.4

 
0.5

 
0.9

 
1.1

Additional benefit costs

 
0.1

 

 
0.3

 

 

 

 

 

$4.1

 

$3.4

 

$8.3

 

$6.8

 

$1.5

 

$0.7

 

$3.0

 

$1.5



401(k) Savings Plans - A significant number of employees participate in defined contribution retirement plans (401(k) savings plans). For the three and six months ended June 30, costs related to the 401(k) savings plans, which are partially based on the participants’ contributions and include allocated costs associated with Corporate Services employees for IPL and WPL, were as follows (in millions):
 
Alliant Energy
 
IPL
 
WPL
 
Three Months
 
Six Months
 
Three Months
 
Six Months
 
Three Months
 
Six Months
 
2016
 
2015
 
2016
 
2015
 
2016
 
2015
 
2016
 
2015
 
2016
 
2015
 
2016
 
2015
401(k) costs

$5.7

 

$5.6

 

$11.9

 

$12.3

 

$2.9

 

$2.9

 

$6.0

 

$6.3

 

$2.6

 

$2.6

 

$5.4

 

$5.5



NOTE 9(b) Equity-based Compensation Plans - All shares, units and awards included below have been adjusted to reflect the common stock split discussed in Note 6.

A summary of compensation expense, including amounts allocated to IPL and WPL, and the related income tax benefits recognized for share-based compensation awards for the three and six months ended June 30 was as follows (in millions):
 
Alliant Energy
 
IPL
 
WPL
 
Three Months
 
Six Months
 
Three Months
 
Six Months
 
Three Months
 
Six Months
 
2016
 
2015
 
2016
 
2015
 
2016
 
2015
 
2016
 
2015
 
2016
 
2015
 
2016
 
2015
Compensation expense

$7.1

 

$2.3

 

$12.4

 

$5.5

 

$3.7

 

$1.2

 

$6.5

 

$2.9

 

$3.1

 

$1.0

 

$5.4

 

$2.4

Income tax benefits
2.9

 
0.9

 
5.1

 
2.2

 
1.6

 
0.5

 
2.7

 
1.2

 
1.3

 
0.4

 
2.2

 
1.0



As of June 30, 2016, total unrecognized compensation cost related to share-based compensation awards was $11.2 million, which is expected to be recognized over a weighted average period of between one and two years. Share-based compensation expense is recognized on a straight-line basis over the requisite service periods and is primarily recorded in “Other operation and maintenance” in the income statements.

Performance Shares and Performance Units - A summary of the performance shares and performance units activity, with amounts representing the target number of awards, was as follows:
 
Performance Shares
 
Performance Units
 
2016
 
2015
 
2016
 
2015
Nonvested awards, January 1
288,430

 
288,848

 
116,412

 
127,330

Granted
68,585

 
90,806

 
23,918

 
35,674

Vested
(98,186
)
 
(91,224
)
 
(42,760
)
 
(45,690
)
Forfeited
(1,230
)
 

 
(4,139
)
 
(666
)
Nonvested awards, June 30
257,599

 
288,430

 
93,431

 
116,648



Granted Awards - For performance units granted in 2016, the final value is based on the closing market price of one share of Alliant Energy’s common stock at the end of the performance period. Compensation expense for performance shares and performance units is recorded ratably over the performance period based on the fair value of the awards at each reporting period.

Vested Awards - During the six months ended June 30, certain performance shares and performance units vested, resulting in payouts (a combination of cash and common stock for the performance shares and cash only for the performance units) as follows:
 
Performance Shares
 
Performance Units
 
2016
 
2015
 
2016
 
2015
 
2013 Grant
 
2012 Grant
 
2013 Grant
 
2012 Grant
Performance awards vested
98,186

 
91,224

 
42,760

 
45,690

Percentage of target number of performance awards
165.0
%
 
167.5
%
 
165.0
%
 
167.5
%
Aggregate payout value (in millions)

$5.1

 

$5.1

 

$1.7

 

$1.6

Payout - cash (in millions)

$2.9

 

$3.2

 

$1.7

 

$1.6

Payout - common stock shares issued
22,408

 
21,950

 
N/A
 
N/A

Fair Value of Awards - Information related to fair values of nonvested performance shares and performance units at June 30, 2016, by year of grant, was as follows:
 
Performance Shares
 
Performance Units
 
2016 Grant
 
2015 Grant
 
2014 Grant
 
2016 Grant
 
2015 Grant
 
2014 Grant
Nonvested awards
67,355

 
90,806

 
99,438

 
22,768

 
33,268

 
37,395

Alliant Energy common stock closing price on June 30, 2016

$39.70

 

$39.70

 

$39.70

 

$39.70

 
N/A
 
N/A
Alliant Energy common stock closing price on grant date
N/A
 
N/A
 
N/A
 
N/A
 

$32.55

 

$26.89

Estimated payout percentage based on performance criteria
118
%
 
150
%
 
155
%
 
118
%
 
150
%
 
155
%
Fair values of each nonvested award

$46.85

 

$59.55

 

$61.54

 

$46.85

 

$48.82

 

$41.67



Performance Contingent Restricted Stock - A summary of the performance contingent restricted stock activity was as follows:
 
2016
 
2015
 
Shares
 
Weighted Average
Grant Date Fair Value
 
Shares
 
Weighted Average
Grant Date Fair Value
Nonvested shares, January 1
190,244

 

$29.59

 
197,624

 

$25.35

Granted

 

 
90,806

 
32.55

Vested (a)

 

 
(98,186
)
 
23.79

Nonvested shares, June 30
190,244

 
29.59

 
190,244

 
29.59



(a)
In 2015, 98,186 performance contingent restricted shares granted in 2013 vested because the specified performance criteria for such shares were met.

Performance Restricted Stock Units and Performance Restricted Units - Alliant Energy granted new types of share-based compensation awards to key employees in the first quarter of 2016 referred to as performance restricted stock units, performance restricted units and key employee performance restricted units. Payouts of these units are based on the achievement of certain performance targets (currently specified growth of consolidated income from continuing operations) during the three-year performance period. The actual number of units that will be paid out upon vesting is dependent upon actual performance and may range from zero to 200% of the target number of units. If performance targets are not met during the performance period, these units are forfeited. Subject to achievement of the performance criteria, payouts of nonvested units are prorated in the event of retirement, death or disability during the first year of the performance period based on time worked during the first year of the period, and are prorated upon involuntary termination without cause based on time worked during the entire period. Subject to achievement of the performance criteria, payouts of units to participants who terminate employment after the first year of the performance period due to retirement, death or disability are not prorated. Participants’ nonvested units are forfeited if the participant voluntarily leaves Alliant Energy or is terminated for cause during the performance period.

Performance Restricted Stock Units - Performance restricted stock units must be paid out in shares and are accounted for as equity awards. Each performance restricted stock unit’s value is based on the closing market price of one share of Alliant Energy’s common stock on the grant date of the award. A summary of the performance restricted stock units activity, with amounts representing the target number of units, was as follows:
 
2016
 
Units
 
Weighted Average
Grant Date Fair Value
Granted
68,585

 

$33.96

Forfeited
(1,230
)
 
33.90

Nonvested units, June 30
67,355

 
33.96



Performance Restricted Units - Performance restricted units must be paid out in cash and are accounted for as liability awards. Each performance restricted unit’s final value is based on the closing market price of one share of Alliant Energy’s common stock at the end of the performance period. Compensation expense is recorded ratably over the performance period based on the fair value of the awards at each reporting period. A summary of the performance restricted units activity, with amounts representing the target number of units, was as follows:
 
2016
Granted
23,918

Forfeited
(1,150
)
Nonvested units, June 30
22,768



Key Employee Performance Restricted Units - Key employee performance restricted units must be paid out in cash and are accounted for as liability awards. Each key employee performance restricted unit’s final value is based on the closing market price of one share of Alliant Energy’s common stock on the grant date of the award. Compensation expense is recorded ratably over the performance period based on a probability assessment of payouts for the awards at each reporting period. A summary of the key employee performance restricted units activity, with amounts representing the target number of units, was as follows:
 
2016
Granted
45,056

Forfeited
(1,238
)
Nonvested units, June 30
43,818



Restricted Stock Units and Restricted Units - Alliant Energy granted new types of share-based compensation awards to key employees in the first quarter of 2016 referred to as restricted stock units and restricted units. Payouts of these units are based on the expiration of a three-year time-vesting period. Payouts of nonvested units are prorated in the event of retirement, death or disability during the first year of the time-vesting period based on time worked during the first year of the period, and are prorated upon involuntary termination without cause based on time worked during the entire period. Upon expiration of the time-vesting period, payouts of units to participants who terminate employment after the first year of the period due to retirement, death or disability are not prorated. Participants’ nonvested units are forfeited if the participant voluntarily leaves Alliant Energy or is terminated for cause during the time-vesting period. Each restricted stock unit’s and restricted unit’s final value is based on the closing market price of one share of Alliant Energy’s common stock at the end of the time-vesting period. Compensation expense is recorded ratably over the performance period based on the fair value of the awards at each reporting period. Restricted stock units can be paid out in shares of Alliant Energy common stock, cash or a combination of cash and stock. Restricted units must be paid out in cash. Alliant Energy assumes it will make future payouts of its restricted stock units and restricted units in cash; therefore, restricted stock units and restricted units are accounted for as liability awards. A summary of the restricted stock units and restricted units activity was as follows:
 
2016
 
Restricted Stock Units
 
Restricted Units
Granted
58,790

 
20,502

Forfeited
(1,054
)
 
(986
)
Nonvested units, June 30
57,736

 
19,516



Performance-Contingent Cash Awards - A summary of the performance-contingent cash awards activity was as follows:
 
2016
 
2015
Nonvested awards, January 1
163,752

 
157,860

Granted

 
82,210

Vested (a)

 
(74,664
)
Forfeited
(3,652
)
 
(1,418
)
Nonvested awards, June 30
160,100

 
163,988


(a)
In 2015, 74,664 performance-contingent cash awards granted in 2013 vested, resulting in cash payouts valued at $2.4 million.
IPL [Member]  
Benefit Plans
BENEFIT PLANS
NOTE 9(a) Pension and Other Postretirement Benefits Plans -
Net Periodic Benefit Costs (Credits) - The components of net periodic benefit costs (credits) for sponsored defined benefit pension and OPEB plans for the three and six months ended June 30 are included in the tables below (in millions). In IPL’s and WPL’s tables below, the defined benefit pension plans costs represent those respective costs for their bargaining unit employees covered under the qualified plans that they sponsor, as well as amounts directly assigned to them related to their current and former non-bargaining employees who are participants in the Alliant Energy and Corporate Services sponsored qualified and non-qualified defined benefit pension plans. In IPL’s and WPL’s tables below, the OPEB plans costs (credits) represent respective costs (credits) for their employees, as well as amounts directly assigned to them related to their current and former non-bargaining employees who are participants in the Corporate Services sponsored OPEB plan.
 
Defined Benefit Pension Plans
 
OPEB Plans
 
Three Months
 
Six Months
 
Three Months
 
Six Months
Alliant Energy
2016
 
2015
 
2016
 
2015
 
2016
 
2015
 
2016
 
2015
Service cost

$3.1

 

$3.9

 

$6.3

 

$7.9

 

$1.3

 

$1.4

 

$2.6

 

$2.8

Interest cost
13.2

 
13.4

 
26.5

 
26.8

 
2.4

 
2.3

 
4.7

 
4.5

Expected return on plan assets
(16.4
)
 
(18.8
)
 
(32.8
)
 
(37.5
)
 
(1.5
)
 
(2.1
)
 
(3.0
)
 
(4.2
)
Amortization of prior service credit

 

 
(0.1
)
 
(0.1
)
 
(1.1
)
 
(2.8
)
 
(2.1
)
 
(5.6
)
Amortization of actuarial loss
9.4

 
8.9

 
18.7

 
17.7

 
1.2

 
1.2

 
2.4

 
2.4

Additional benefit costs

 
0.1

 

 
0.3

 

 

 

 

 

$9.3

 

$7.5

 

$18.6

 

$15.1

 

$2.3

 

$—

 

$4.6

 

($0.1
)
 
Defined Benefit Pension Plans
 
OPEB Plans
 
Three Months
 
Six Months
 
Three Months
 
Six Months
IPL
2016
 
2015
 
2016
 
2015
 
2016
 
2015
 
2016
 
2015
Service cost

$1.9

 

$2.2

 

$3.8

 

$4.4

 

$0.6

 

$0.6

 

$1.2

 

$1.2

Interest cost
6.2

 
6.3

 
12.3

 
12.5

 
0.9

 
1.0

 
1.9

 
1.9

Expected return on plan assets
(7.8
)
 
(9.0
)
 
(15.5
)
 
(17.9
)
 
(1.2
)
 
(1.4
)
 
(2.2
)
 
(2.8
)
Amortization of prior service credit
(0.1
)
 
(0.1
)
 
(0.1
)
 
(0.1
)
 
(0.6
)
 
(1.6
)
 
(1.3
)
 
(3.1
)
Amortization of actuarial loss
4.1

 
3.9

 
8.2

 
7.7

 
0.7

 
0.5

 
1.3

 
1.1

 

$4.3

 

$3.3

 

$8.7

 

$6.6

 

$0.4

 

($0.9
)
 

$0.9

 

($1.7
)
 
Defined Benefit Pension Plans
 
OPEB Plans
 
Three Months
 
Six Months
 
Three Months
 
Six Months
WPL
2016
 
2015
 
2016
 
2015
 
2016
 
2015
 
2016
 
2015
Service cost

$1.2

 

$1.5

 

$2.4

 

$2.9

 

$0.5

 

$0.5

 

$1.0

 

$1.1

Interest cost
5.6

 
5.7

 
11.2

 
11.3

 
1.0

 
0.9

 
1.9

 
1.8

Expected return on plan assets
(7.1
)
 
(8.1
)
 
(14.2
)
 
(16.2
)
 
(0.2
)
 
(0.4
)
 
(0.4
)
 
(0.8
)
Amortization of prior service cost (credit)

 

 
0.1

 
0.1

 
(0.2
)
 
(0.8
)
 
(0.4
)
 
(1.7
)
Amortization of actuarial loss
4.4

 
4.2

 
8.8

 
8.4

 
0.4

 
0.5

 
0.9

 
1.1

Additional benefit costs

 
0.1

 

 
0.3

 

 

 

 

 

$4.1

 

$3.4

 

$8.3

 

$6.8

 

$1.5

 

$0.7

 

$3.0

 

$1.5



401(k) Savings Plans - A significant number of employees participate in defined contribution retirement plans (401(k) savings plans). For the three and six months ended June 30, costs related to the 401(k) savings plans, which are partially based on the participants’ contributions and include allocated costs associated with Corporate Services employees for IPL and WPL, were as follows (in millions):
 
Alliant Energy
 
IPL
 
WPL
 
Three Months
 
Six Months
 
Three Months
 
Six Months
 
Three Months
 
Six Months
 
2016
 
2015
 
2016
 
2015
 
2016
 
2015
 
2016
 
2015
 
2016
 
2015
 
2016
 
2015
401(k) costs

$5.7

 

$5.6

 

$11.9

 

$12.3

 

$2.9

 

$2.9

 

$6.0

 

$6.3

 

$2.6

 

$2.6

 

$5.4

 

$5.5



NOTE 9(b) Equity-based Compensation Plans - All shares, units and awards included below have been adjusted to reflect the common stock split discussed in Note 6.

A summary of compensation expense, including amounts allocated to IPL and WPL, and the related income tax benefits recognized for share-based compensation awards for the three and six months ended June 30 was as follows (in millions):
 
Alliant Energy
 
IPL
 
WPL
 
Three Months
 
Six Months
 
Three Months
 
Six Months
 
Three Months
 
Six Months
 
2016
 
2015
 
2016
 
2015
 
2016
 
2015
 
2016
 
2015
 
2016
 
2015
 
2016
 
2015
Compensation expense

$7.1

 

$2.3

 

$12.4

 

$5.5

 

$3.7

 

$1.2

 

$6.5

 

$2.9

 

$3.1

 

$1.0

 

$5.4

 

$2.4

Income tax benefits
2.9

 
0.9

 
5.1

 
2.2

 
1.6

 
0.5

 
2.7

 
1.2

 
1.3

 
0.4

 
2.2

 
1.0



As of June 30, 2016, total unrecognized compensation cost related to share-based compensation awards was $11.2 million, which is expected to be recognized over a weighted average period of between one and two years. Share-based compensation expense is recognized on a straight-line basis over the requisite service periods and is primarily recorded in “Other operation and maintenance” in the income statements.

Performance Shares and Performance Units - A summary of the performance shares and performance units activity, with amounts representing the target number of awards, was as follows:
 
Performance Shares
 
Performance Units
 
2016
 
2015
 
2016
 
2015
Nonvested awards, January 1
288,430

 
288,848

 
116,412

 
127,330

Granted
68,585

 
90,806

 
23,918

 
35,674

Vested
(98,186
)
 
(91,224
)
 
(42,760
)
 
(45,690
)
Forfeited
(1,230
)
 

 
(4,139
)
 
(666
)
Nonvested awards, June 30
257,599

 
288,430

 
93,431

 
116,648



Granted Awards - For performance units granted in 2016, the final value is based on the closing market price of one share of Alliant Energy’s common stock at the end of the performance period. Compensation expense for performance shares and performance units is recorded ratably over the performance period based on the fair value of the awards at each reporting period.

Vested Awards - During the six months ended June 30, certain performance shares and performance units vested, resulting in payouts (a combination of cash and common stock for the performance shares and cash only for the performance units) as follows:
 
Performance Shares
 
Performance Units
 
2016
 
2015
 
2016
 
2015
 
2013 Grant
 
2012 Grant
 
2013 Grant
 
2012 Grant
Performance awards vested
98,186

 
91,224

 
42,760

 
45,690

Percentage of target number of performance awards
165.0
%
 
167.5
%
 
165.0
%
 
167.5
%
Aggregate payout value (in millions)

$5.1

 

$5.1

 

$1.7

 

$1.6

Payout - cash (in millions)

$2.9

 

$3.2

 

$1.7

 

$1.6

Payout - common stock shares issued
22,408

 
21,950

 
N/A
 
N/A

Fair Value of Awards - Information related to fair values of nonvested performance shares and performance units at June 30, 2016, by year of grant, was as follows:
 
Performance Shares
 
Performance Units
 
2016 Grant
 
2015 Grant
 
2014 Grant
 
2016 Grant
 
2015 Grant
 
2014 Grant
Nonvested awards
67,355

 
90,806

 
99,438

 
22,768

 
33,268

 
37,395

Alliant Energy common stock closing price on June 30, 2016

$39.70

 

$39.70

 

$39.70

 

$39.70

 
N/A
 
N/A
Alliant Energy common stock closing price on grant date
N/A
 
N/A
 
N/A
 
N/A
 

$32.55

 

$26.89

Estimated payout percentage based on performance criteria
118
%
 
150
%
 
155
%
 
118
%
 
150
%
 
155
%
Fair values of each nonvested award

$46.85

 

$59.55

 

$61.54

 

$46.85

 

$48.82

 

$41.67



Performance Contingent Restricted Stock - A summary of the performance contingent restricted stock activity was as follows:
 
2016
 
2015
 
Shares
 
Weighted Average
Grant Date Fair Value
 
Shares
 
Weighted Average
Grant Date Fair Value
Nonvested shares, January 1
190,244

 

$29.59

 
197,624

 

$25.35

Granted

 

 
90,806

 
32.55

Vested (a)

 

 
(98,186
)
 
23.79

Nonvested shares, June 30
190,244

 
29.59

 
190,244

 
29.59



(a)
In 2015, 98,186 performance contingent restricted shares granted in 2013 vested because the specified performance criteria for such shares were met.

Performance Restricted Stock Units and Performance Restricted Units - Alliant Energy granted new types of share-based compensation awards to key employees in the first quarter of 2016 referred to as performance restricted stock units, performance restricted units and key employee performance restricted units. Payouts of these units are based on the achievement of certain performance targets (currently specified growth of consolidated income from continuing operations) during the three-year performance period. The actual number of units that will be paid out upon vesting is dependent upon actual performance and may range from zero to 200% of the target number of units. If performance targets are not met during the performance period, these units are forfeited. Subject to achievement of the performance criteria, payouts of nonvested units are prorated in the event of retirement, death or disability during the first year of the performance period based on time worked during the first year of the period, and are prorated upon involuntary termination without cause based on time worked during the entire period. Subject to achievement of the performance criteria, payouts of units to participants who terminate employment after the first year of the performance period due to retirement, death or disability are not prorated. Participants’ nonvested units are forfeited if the participant voluntarily leaves Alliant Energy or is terminated for cause during the performance period.

Performance Restricted Stock Units - Performance restricted stock units must be paid out in shares and are accounted for as equity awards. Each performance restricted stock unit’s value is based on the closing market price of one share of Alliant Energy’s common stock on the grant date of the award. A summary of the performance restricted stock units activity, with amounts representing the target number of units, was as follows:
 
2016
 
Units
 
Weighted Average
Grant Date Fair Value
Granted
68,585

 

$33.96

Forfeited
(1,230
)
 
33.90

Nonvested units, June 30
67,355

 
33.96



Performance Restricted Units - Performance restricted units must be paid out in cash and are accounted for as liability awards. Each performance restricted unit’s final value is based on the closing market price of one share of Alliant Energy’s common stock at the end of the performance period. Compensation expense is recorded ratably over the performance period based on the fair value of the awards at each reporting period. A summary of the performance restricted units activity, with amounts representing the target number of units, was as follows:
 
2016
Granted
23,918

Forfeited
(1,150
)
Nonvested units, June 30
22,768



Key Employee Performance Restricted Units - Key employee performance restricted units must be paid out in cash and are accounted for as liability awards. Each key employee performance restricted unit’s final value is based on the closing market price of one share of Alliant Energy’s common stock on the grant date of the award. Compensation expense is recorded ratably over the performance period based on a probability assessment of payouts for the awards at each reporting period. A summary of the key employee performance restricted units activity, with amounts representing the target number of units, was as follows:
 
2016
Granted
45,056

Forfeited
(1,238
)
Nonvested units, June 30
43,818



Restricted Stock Units and Restricted Units - Alliant Energy granted new types of share-based compensation awards to key employees in the first quarter of 2016 referred to as restricted stock units and restricted units. Payouts of these units are based on the expiration of a three-year time-vesting period. Payouts of nonvested units are prorated in the event of retirement, death or disability during the first year of the time-vesting period based on time worked during the first year of the period, and are prorated upon involuntary termination without cause based on time worked during the entire period. Upon expiration of the time-vesting period, payouts of units to participants who terminate employment after the first year of the period due to retirement, death or disability are not prorated. Participants’ nonvested units are forfeited if the participant voluntarily leaves Alliant Energy or is terminated for cause during the time-vesting period. Each restricted stock unit’s and restricted unit’s final value is based on the closing market price of one share of Alliant Energy’s common stock at the end of the time-vesting period. Compensation expense is recorded ratably over the performance period based on the fair value of the awards at each reporting period. Restricted stock units can be paid out in shares of Alliant Energy common stock, cash or a combination of cash and stock. Restricted units must be paid out in cash. Alliant Energy assumes it will make future payouts of its restricted stock units and restricted units in cash; therefore, restricted stock units and restricted units are accounted for as liability awards. A summary of the restricted stock units and restricted units activity was as follows:
 
2016
 
Restricted Stock Units
 
Restricted Units
Granted
58,790

 
20,502

Forfeited
(1,054
)
 
(986
)
Nonvested units, June 30
57,736

 
19,516



Performance-Contingent Cash Awards - A summary of the performance-contingent cash awards activity was as follows:
 
2016
 
2015
Nonvested awards, January 1
163,752

 
157,860

Granted

 
82,210

Vested (a)

 
(74,664
)
Forfeited
(3,652
)
 
(1,418
)
Nonvested awards, June 30
160,100

 
163,988


(a)
In 2015, 74,664 performance-contingent cash awards granted in 2013 vested, resulting in cash payouts valued at $2.4 million.
WPL [Member]  
Benefit Plans
BENEFIT PLANS
NOTE 9(a) Pension and Other Postretirement Benefits Plans -
Net Periodic Benefit Costs (Credits) - The components of net periodic benefit costs (credits) for sponsored defined benefit pension and OPEB plans for the three and six months ended June 30 are included in the tables below (in millions). In IPL’s and WPL’s tables below, the defined benefit pension plans costs represent those respective costs for their bargaining unit employees covered under the qualified plans that they sponsor, as well as amounts directly assigned to them related to their current and former non-bargaining employees who are participants in the Alliant Energy and Corporate Services sponsored qualified and non-qualified defined benefit pension plans. In IPL’s and WPL’s tables below, the OPEB plans costs (credits) represent respective costs (credits) for their employees, as well as amounts directly assigned to them related to their current and former non-bargaining employees who are participants in the Corporate Services sponsored OPEB plan.
 
Defined Benefit Pension Plans
 
OPEB Plans
 
Three Months
 
Six Months
 
Three Months
 
Six Months
Alliant Energy
2016
 
2015
 
2016
 
2015
 
2016
 
2015
 
2016
 
2015
Service cost

$3.1

 

$3.9

 

$6.3

 

$7.9

 

$1.3

 

$1.4

 

$2.6

 

$2.8

Interest cost
13.2

 
13.4

 
26.5

 
26.8

 
2.4

 
2.3

 
4.7

 
4.5

Expected return on plan assets
(16.4
)
 
(18.8
)
 
(32.8
)
 
(37.5
)
 
(1.5
)
 
(2.1
)
 
(3.0
)
 
(4.2
)
Amortization of prior service credit

 

 
(0.1
)
 
(0.1
)
 
(1.1
)
 
(2.8
)
 
(2.1
)
 
(5.6
)
Amortization of actuarial loss
9.4

 
8.9

 
18.7

 
17.7

 
1.2

 
1.2

 
2.4

 
2.4

Additional benefit costs

 
0.1

 

 
0.3

 

 

 

 

 

$9.3

 

$7.5

 

$18.6

 

$15.1

 

$2.3

 

$—

 

$4.6

 

($0.1
)
 
Defined Benefit Pension Plans
 
OPEB Plans
 
Three Months
 
Six Months
 
Three Months
 
Six Months
IPL
2016
 
2015
 
2016
 
2015
 
2016
 
2015
 
2016
 
2015
Service cost

$1.9

 

$2.2

 

$3.8

 

$4.4

 

$0.6

 

$0.6

 

$1.2

 

$1.2

Interest cost
6.2

 
6.3

 
12.3

 
12.5

 
0.9

 
1.0

 
1.9

 
1.9

Expected return on plan assets
(7.8
)
 
(9.0
)
 
(15.5
)
 
(17.9
)
 
(1.2
)
 
(1.4
)
 
(2.2
)
 
(2.8
)
Amortization of prior service credit
(0.1
)
 
(0.1
)
 
(0.1
)
 
(0.1
)
 
(0.6
)
 
(1.6
)
 
(1.3
)
 
(3.1
)
Amortization of actuarial loss
4.1

 
3.9

 
8.2

 
7.7

 
0.7

 
0.5

 
1.3

 
1.1

 

$4.3

 

$3.3

 

$8.7

 

$6.6

 

$0.4

 

($0.9
)
 

$0.9

 

($1.7
)
 
Defined Benefit Pension Plans
 
OPEB Plans
 
Three Months
 
Six Months
 
Three Months
 
Six Months
WPL
2016
 
2015
 
2016
 
2015
 
2016
 
2015
 
2016
 
2015
Service cost

$1.2

 

$1.5

 

$2.4

 

$2.9

 

$0.5

 

$0.5

 

$1.0

 

$1.1

Interest cost
5.6

 
5.7

 
11.2

 
11.3

 
1.0

 
0.9

 
1.9

 
1.8

Expected return on plan assets
(7.1
)
 
(8.1
)
 
(14.2
)
 
(16.2
)
 
(0.2
)
 
(0.4
)
 
(0.4
)
 
(0.8
)
Amortization of prior service cost (credit)

 

 
0.1

 
0.1

 
(0.2
)
 
(0.8
)
 
(0.4
)
 
(1.7
)
Amortization of actuarial loss
4.4

 
4.2

 
8.8

 
8.4

 
0.4

 
0.5

 
0.9

 
1.1

Additional benefit costs

 
0.1

 

 
0.3

 

 

 

 

 

$4.1

 

$3.4

 

$8.3

 

$6.8

 

$1.5

 

$0.7

 

$3.0

 

$1.5



401(k) Savings Plans - A significant number of employees participate in defined contribution retirement plans (401(k) savings plans). For the three and six months ended June 30, costs related to the 401(k) savings plans, which are partially based on the participants’ contributions and include allocated costs associated with Corporate Services employees for IPL and WPL, were as follows (in millions):
 
Alliant Energy
 
IPL
 
WPL
 
Three Months
 
Six Months
 
Three Months
 
Six Months
 
Three Months
 
Six Months
 
2016
 
2015
 
2016
 
2015
 
2016
 
2015
 
2016
 
2015
 
2016
 
2015
 
2016
 
2015
401(k) costs

$5.7

 

$5.6

 

$11.9

 

$12.3

 

$2.9

 

$2.9

 

$6.0

 

$6.3

 

$2.6

 

$2.6

 

$5.4

 

$5.5



NOTE 9(b) Equity-based Compensation Plans - All shares, units and awards included below have been adjusted to reflect the common stock split discussed in Note 6.

A summary of compensation expense, including amounts allocated to IPL and WPL, and the related income tax benefits recognized for share-based compensation awards for the three and six months ended June 30 was as follows (in millions):
 
Alliant Energy
 
IPL
 
WPL
 
Three Months
 
Six Months
 
Three Months
 
Six Months
 
Three Months
 
Six Months
 
2016
 
2015
 
2016
 
2015
 
2016
 
2015
 
2016
 
2015
 
2016
 
2015
 
2016
 
2015
Compensation expense

$7.1

 

$2.3

 

$12.4

 

$5.5

 

$3.7

 

$1.2

 

$6.5

 

$2.9

 

$3.1

 

$1.0

 

$5.4

 

$2.4

Income tax benefits
2.9

 
0.9

 
5.1

 
2.2

 
1.6

 
0.5

 
2.7

 
1.2

 
1.3

 
0.4

 
2.2

 
1.0



As of June 30, 2016, total unrecognized compensation cost related to share-based compensation awards was $11.2 million, which is expected to be recognized over a weighted average period of between one and two years. Share-based compensation expense is recognized on a straight-line basis over the requisite service periods and is primarily recorded in “Other operation and maintenance” in the income statements.

Performance Shares and Performance Units - A summary of the performance shares and performance units activity, with amounts representing the target number of awards, was as follows:
 
Performance Shares
 
Performance Units
 
2016
 
2015
 
2016
 
2015
Nonvested awards, January 1
288,430

 
288,848

 
116,412

 
127,330

Granted
68,585

 
90,806

 
23,918

 
35,674

Vested
(98,186
)
 
(91,224
)
 
(42,760
)
 
(45,690
)
Forfeited
(1,230
)
 

 
(4,139
)
 
(666
)
Nonvested awards, June 30
257,599

 
288,430

 
93,431

 
116,648



Granted Awards - For performance units granted in 2016, the final value is based on the closing market price of one share of Alliant Energy’s common stock at the end of the performance period. Compensation expense for performance shares and performance units is recorded ratably over the performance period based on the fair value of the awards at each reporting period.

Vested Awards - During the six months ended June 30, certain performance shares and performance units vested, resulting in payouts (a combination of cash and common stock for the performance shares and cash only for the performance units) as follows:
 
Performance Shares
 
Performance Units
 
2016
 
2015
 
2016
 
2015
 
2013 Grant
 
2012 Grant
 
2013 Grant
 
2012 Grant
Performance awards vested
98,186

 
91,224

 
42,760

 
45,690

Percentage of target number of performance awards
165.0
%
 
167.5
%
 
165.0
%
 
167.5
%
Aggregate payout value (in millions)

$5.1

 

$5.1

 

$1.7

 

$1.6

Payout - cash (in millions)

$2.9

 

$3.2

 

$1.7

 

$1.6

Payout - common stock shares issued
22,408

 
21,950

 
N/A
 
N/A

Fair Value of Awards - Information related to fair values of nonvested performance shares and performance units at June 30, 2016, by year of grant, was as follows:
 
Performance Shares
 
Performance Units
 
2016 Grant
 
2015 Grant
 
2014 Grant
 
2016 Grant
 
2015 Grant
 
2014 Grant
Nonvested awards
67,355

 
90,806

 
99,438

 
22,768

 
33,268

 
37,395

Alliant Energy common stock closing price on June 30, 2016

$39.70

 

$39.70

 

$39.70

 

$39.70

 
N/A
 
N/A
Alliant Energy common stock closing price on grant date
N/A
 
N/A
 
N/A
 
N/A
 

$32.55

 

$26.89

Estimated payout percentage based on performance criteria
118
%
 
150
%
 
155
%
 
118
%
 
150
%
 
155
%
Fair values of each nonvested award

$46.85

 

$59.55

 

$61.54

 

$46.85

 

$48.82

 

$41.67



Performance Contingent Restricted Stock - A summary of the performance contingent restricted stock activity was as follows:
 
2016
 
2015
 
Shares
 
Weighted Average
Grant Date Fair Value
 
Shares
 
Weighted Average
Grant Date Fair Value
Nonvested shares, January 1
190,244

 

$29.59

 
197,624

 

$25.35

Granted

 

 
90,806

 
32.55

Vested (a)

 

 
(98,186
)
 
23.79

Nonvested shares, June 30
190,244

 
29.59

 
190,244

 
29.59



(a)
In 2015, 98,186 performance contingent restricted shares granted in 2013 vested because the specified performance criteria for such shares were met.

Performance Restricted Stock Units and Performance Restricted Units - Alliant Energy granted new types of share-based compensation awards to key employees in the first quarter of 2016 referred to as performance restricted stock units, performance restricted units and key employee performance restricted units. Payouts of these units are based on the achievement of certain performance targets (currently specified growth of consolidated income from continuing operations) during the three-year performance period. The actual number of units that will be paid out upon vesting is dependent upon actual performance and may range from zero to 200% of the target number of units. If performance targets are not met during the performance period, these units are forfeited. Subject to achievement of the performance criteria, payouts of nonvested units are prorated in the event of retirement, death or disability during the first year of the performance period based on time worked during the first year of the period, and are prorated upon involuntary termination without cause based on time worked during the entire period. Subject to achievement of the performance criteria, payouts of units to participants who terminate employment after the first year of the performance period due to retirement, death or disability are not prorated. Participants’ nonvested units are forfeited if the participant voluntarily leaves Alliant Energy or is terminated for cause during the performance period.

Performance Restricted Stock Units - Performance restricted stock units must be paid out in shares and are accounted for as equity awards. Each performance restricted stock unit’s value is based on the closing market price of one share of Alliant Energy’s common stock on the grant date of the award. A summary of the performance restricted stock units activity, with amounts representing the target number of units, was as follows:
 
2016
 
Units
 
Weighted Average
Grant Date Fair Value
Granted
68,585

 

$33.96

Forfeited
(1,230
)
 
33.90

Nonvested units, June 30
67,355

 
33.96



Performance Restricted Units - Performance restricted units must be paid out in cash and are accounted for as liability awards. Each performance restricted unit’s final value is based on the closing market price of one share of Alliant Energy’s common stock at the end of the performance period. Compensation expense is recorded ratably over the performance period based on the fair value of the awards at each reporting period. A summary of the performance restricted units activity, with amounts representing the target number of units, was as follows:
 
2016
Granted
23,918

Forfeited
(1,150
)
Nonvested units, June 30
22,768



Key Employee Performance Restricted Units - Key employee performance restricted units must be paid out in cash and are accounted for as liability awards. Each key employee performance restricted unit’s final value is based on the closing market price of one share of Alliant Energy’s common stock on the grant date of the award. Compensation expense is recorded ratably over the performance period based on a probability assessment of payouts for the awards at each reporting period. A summary of the key employee performance restricted units activity, with amounts representing the target number of units, was as follows:
 
2016
Granted
45,056

Forfeited
(1,238
)
Nonvested units, June 30
43,818



Restricted Stock Units and Restricted Units - Alliant Energy granted new types of share-based compensation awards to key employees in the first quarter of 2016 referred to as restricted stock units and restricted units. Payouts of these units are based on the expiration of a three-year time-vesting period. Payouts of nonvested units are prorated in the event of retirement, death or disability during the first year of the time-vesting period based on time worked during the first year of the period, and are prorated upon involuntary termination without cause based on time worked during the entire period. Upon expiration of the time-vesting period, payouts of units to participants who terminate employment after the first year of the period due to retirement, death or disability are not prorated. Participants’ nonvested units are forfeited if the participant voluntarily leaves Alliant Energy or is terminated for cause during the time-vesting period. Each restricted stock unit’s and restricted unit’s final value is based on the closing market price of one share of Alliant Energy’s common stock at the end of the time-vesting period. Compensation expense is recorded ratably over the performance period based on the fair value of the awards at each reporting period. Restricted stock units can be paid out in shares of Alliant Energy common stock, cash or a combination of cash and stock. Restricted units must be paid out in cash. Alliant Energy assumes it will make future payouts of its restricted stock units and restricted units in cash; therefore, restricted stock units and restricted units are accounted for as liability awards. A summary of the restricted stock units and restricted units activity was as follows:
 
2016
 
Restricted Stock Units
 
Restricted Units
Granted
58,790

 
20,502

Forfeited
(1,054
)
 
(986
)
Nonvested units, June 30
57,736

 
19,516



Performance-Contingent Cash Awards - A summary of the performance-contingent cash awards activity was as follows:
 
2016
 
2015
Nonvested awards, January 1
163,752

 
157,860

Granted

 
82,210

Vested (a)

 
(74,664
)
Forfeited
(3,652
)
 
(1,418
)
Nonvested awards, June 30
160,100

 
163,988


(a)
In 2015, 74,664 performance-contingent cash awards granted in 2013 vested, resulting in cash payouts valued at $2.4 million.