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v3.19.3.a.u2

Share and Unit-based Plans (Tables) | 12 Months Ended
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Dec. 31, 2019
Share-based Payment Arrangement [Abstract] |
Summary of Activity of Non-vested Stock Units | The following table summarizes the activity of non-vested stock units during the years ended December 31, 2019, 2018 and 2017:
| 2019 |  |  |  | 2018 |  |  |  | 2017 |  |
| Units |  | Weighted Average Grant Date Fair Value |  | Units |  | Weighted Average Grant Date Fair Value |  | Units |  | Weighted Average Grant Date Fair Value
Balance at beginning of year | 129,457 |  |  | $ | 64.21 |  |  | 151,355 |  |  | $ | 73.32 |  |  | 148,428 |  |  | $ | 78.53 |
Granted | 160,932 |  |  | 37.44 |  |  | 87,983 |  |  | 58.79 |  |  | 86,827 |  |  | 66.46 |
Vested | (85,157) |  |  | 62.84 |  |  | (108,991) |  |  | 74.04 |  |  | (81,205) |  |  | 75.62 |
Forfeited | (5,245) |  |  | 51.48 |  |  | (890) |  |  | 68.81 |  |  | (2,695) |  |  | 69.57 |
Balance at end of year | 199,987 |  |  | $ | 43.59 |  |  | 129,457 |  |  | $ | 64.21 |  |  | 151,355 |  |  | $ | 73.32 |
Summary of Activity of SARs Awards | The following table summarizes the activity of SARs awards during the years ended December 31, 2019, 2018 and 2017:
| 2019 |  |  |  | 2018 |  |  |  | 2017 |  |
| Units |  | Weighted Average Exercise Price |  | Units |  | Weighted Average Exercise Price |  | Units |  | Weighted Average Exercise Price
Balance at beginning of year | — |  |  | $ | — |  |  | 235,439 |  |  | $ | 53.83 |  |  | 284,146 |  |  | $ | 53.85 |
Granted | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  |  |
Exercised | — |  |  | — |  |  | (235,439) |  |  | 53.83 |  |  | (48,707) |  |  | 53.95 |
Balance at end of year | — |  |  | $ | — |  |  | — |  |  | $ | — |  |  | 235,439 |  |  | $ | 53.83 |
Schedule of LTIP Units Granted | The Company has granted the following LTIP units during the years ended December 31, 2019, 2018 and 2017:
Grant Date |  | Units |  | Type |  | Fair Value per LTIP Unit |  | Vest Date
1/1/2017 |  | 66,079 |  |  | Service-based |  | $ | 70.84 |  |  | 12/31/2019
1/1/2017 |  | 297,849 |  |  | Market-indexed |  | $ | 47.15 |  |  | 12/31/2019
3/3/2017 |  | 134,742 |  |  | Service-based |  | $ | 66.57 |  |  | 3/3/2017
6/1/2017 |  | 1,522 |  |  | Service-based |  | $ | 58.31 |  |  | 5/29/2020
6/1/2017 |  | 6,714 |  |  | Market-indexed |  | $ | 39.66 |  |  | 5/29/2020
|  | 506,906 |  |  |  |  |  |  |
1/1/2018 |  | 65,466 |  |  | Service-based |  | $ | 65.68 |  |  | 12/31/2020
1/1/2018 |  | 291,326 |  |  | Market-indexed |  | $ | 44.28 |  |  | 12/31/2020
1/29/2018 |  | 13,632 |  |  | Service-based |  | $ | 66.02 |  |  | 2/1/2022
1/29/2018 |  | 1,893 |  |  | Service-based |  | $ | 66.02 |  |  | 12/31/2020
1/29/2018 |  | 7,775 |  |  | Market-indexed |  | $ | 48.23 |  |  | 12/31/2020
3/2/2018 |  | 99,407 |  |  | Service-based |  | $ | 59.04 |  |  | 3/2/2018
4/26/2018 |  | 89,637 |  |  | Service-based |  | $ | 55.78 |  |  | 4/26/2018
|  | 569,136 |  |  |  |  |  |  |
1/1/2019 |  | 81,732 |  |  | Service-based |  | $ | 43.28 |  |  | 12/31/2021
1/1/2019 |  | 250,852 |  |  | Market-indexed |  | $ | 29.25 |  |  | 12/31/2021
9/1/2019 |  | 4,393 |  |  | Service-based |  | $ | 28.53 |  |  | 8/31/2022
9/1/2019 |  | 6,454 |  |  | Market-indexed |  | $ | 19.42 |  |  | 8/31/2022
|  | 343,431 |  |  |  |  |  |  |
Schedule LTIP Units Valuation Assumptions | The fair value of the market-indexed LTIP Units (Level 3) were estimated on the date of grant using a Monte Carlo Simulation model that based on the following assumptions:
Grant Date |  | Risk Free Interest Rate |  | Expected Volatility
1/1/2017 |  | 1.49 | % |  | 20.75 | %
6/1/2017 |  | 1.45 | % |  | 21.40 | %
1/1/2018 |  | 1.98 | % |  | 23.38 | %
1/29/2018 |  | 2.25 | % |  | 23.86 | %
1/1/2019 |  | 2.46 | % |  | 23.52 | %
9/1/2019 |  | 1.42 | % |  | 24.91 | %
Summary of Activity of Stock Options | The following table summarizes the activity of the non-vested LTIP Units during the years ended December 31, 2019, 2018 and 2017:
| 2019 |  |  |  | 2018 |  |  |  | 2017 |  |
| Units |  | Weighted Average Grant Date Fair Value |  | Units |  | Weighted Average Grant Date Fair Value |  | Units |  | Weighted Average Grant Date Fair Value
Balance at beginning of year | 661,578 |  |  | $ | 48.38 |  |  | 636,632 |  |  | $ | 52.36 |  |  | 322,572 |  |  | $ | 58.18 |
Granted | 343,431 |  |  | 32.40 |  |  | 569,136 |  |  | 51.78 |  |  | 506,906 |  |  | 55.33 |
Vested | (76,306) |  |  | 59.27 |  |  | (253,625) |  |  | 61.17 |  |  | (192,846) |  |  | 69.93 |
Forfeited | (312,484) |  |  | 46.55 |  |  | (290,565) |  |  | 52.58 |  |  | — |  |  | — |
Balance at end of year | 616,219 |  |  | $ | 39.04 |  |  | 661,578 |  |  | $ | 48.38 |  |  | 636,632 |  |  | $ | 52.36 |
The following table summarizes the activity of stock options for the years ended December 31, 2019, 2018 and 2017:
| 2019 |  |  |  | 2018 |  |  |  | 2017 |  |
| Options |  | Weighted Average Exercise Price |  | Options |  | Weighted Average Exercise Price |  | Options |  | Weighted Average Exercise Price
Balance at beginning of year | 35,565 |  |  | $ | 57.32 |  |  | 35,565 |  |  | $ | 57.32 |  |  | 10,565 |  |  | $ | 56.77 |
Granted | — |  |  | — |  |  | — |  |  | — |  |  | 25,000 |  |  | 57.55 |
Exercised | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Balance at end of year | 35,565 |  |  | $ | 57.32 |  |  | 35,565 |  |  | $ | 57.32 |  |  | 35,565 |  |  | $ | 57.32 |
Summary of Activity of Non-vested Phantom Stock Units | The following table summarizes the activity of the non-vested phantom stock units for the years ended December 31, 2019, 2018 and 2017:
| 2019 |  |  |  | 2018 |  |  |  | 2017 |  |
| Stock Units |  | Weighted Average Grant Date Fair Value |  | Stock Units |  | Weighted Average Grant Date Fair Value |  | Stock Units |  | Weighted Average Grant Date Fair Value
Balance at beginning of year | — |  |  | $ | — |  |  | 4,054 |  |  | $ | 79.82 |  |  | 5,845 |  |  | $ | 81.47 |
Granted | 23,690 |  |  | 40.26 |  |  | 10,380 |  |  | 49.55 |  |  | 8,760 |  |  | 68.93 |
Vested | (16,474) |  |  | 38.94 |  |  | (12,193) |  |  | 54.40 |  |  | (10,551) |  |  | 71.69 |
Forfeited | — |  |  | — |  |  | (2,241) |  |  | 77.91 |  |  | — |  |  | — |
Balance at end of year | 7,216 |  |  | $ | 43.29 |  |  | — |  |  | $ | — |  |  | 4,054 |  |  | $ | 79.82 |
Compensation Cost Under the Share and Unit-based Plans | The following summarizes the compensation cost under the share and unit-based plans for the years ended December 31, 2019, 2018 and 2017:
| 2019 |  | 2018 |  | 2017
Stock units | $ | 4,598 |  |  | $ | 6,355 |  |  | $ | 6,045 |
LTIP units | 11,372 |  |  | 26,311 |  |  | 30,161 |
Stock options | 51 |  |  | 125 |  |  | 85 |
Phantom stock units | 702 |  |  | 760 |  |  | 714 |
| $ | 16,723 |  |  | $ | 33,551 |  |  | $ | 37,005 |

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