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Share-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2020

Share-based Payment Arrangement [Abstract]

Valuation assumptions

			Year Ended December 31,
			2020						2019						2018
Dividend yield			—		%				—		%				—		%
Expected volatility			16.6 %						18.1		%				21.3		%
Risk free interest rate			1.2 %						2.5		%				2.8		%
Expected option life			6.0 years						6.0 years						6.0 years

Option activity

A summary of stock option and SAR activity under the Company’s Long Term Incentive and Share Award Plans during 2020 is presented below:

			Year Ended December 31, 2020
			Number of Options / SARs						Weighted Average Exercise Price						Weighted Average Contractual Term						Aggregate Intrinsic Value
Outstanding, beginning of year			18,853,018						$	20.94
Granted			1,121,833						$	42.34
Exercised			(1,981,216)						$	10.92
Forfeited or expired			(154,302)						$	30.13
Outstanding, end of year			17,839,333						$	23.32					4.74						$	234,659
Exercisable, end of year			15,132,810						$	21.30					4.10						$	223,908

Weighted average grant date fair value

			Year Ended December 31,
			2020						2019						2018
Weighted average grant date fair value			$	8.14					$	7.90					$	7.50
Aggregate intrinsic value of Options/SARs exercised			$	59,723					$	51,350					$	43,468

Unvested restricted share and unit activity

A summary of restricted share and restricted unit activity under the Company’s Long Term Incentive and Share Award Plans for 2020 is presented below:

			Restricted Common Shares						Restricted Unit Awards
Unvested Shares:
Unvested balance, beginning of year			1,045,921						1,563,012
Granted			1,328,033						207,297
Vested			(697,090)						(620,905)
Forfeited			(41,019)						(27,685)
Unvested balance, end of year			1,635,845						1,121,719
Weighted Average Grant Date Fair Value:
Unvested balance, beginning of year			$	31.02					$	30.07
Granted			$	37.58					$	37.32
Vested			$	30.86					$	29.99
Forfeited			$	33.91					$	30.76
Unvested balance, end of year			$	36.34					$	31.43

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Performance shares and units, valuation assumptions

			Year Ended December 31,
			2020						2019						2018
Expected volatility			18.1 %						17.1 %						16.2 %
Risk free interest rate			1.1 %						2.5 %						2.6 %

Unvested performance share and unit activity

			Performance Shares						Performance Units
Unvested Shares:
Unvested balance, beginning of year			1,400,914						23,767
Granted			548,906						8,298
Vested			—						—
Forfeited			(98,438)						—
Unvested balance, end of year			1,851,382						32,065
Weighted Average Grant Date Fair Value:
Unvested balance, beginning of year			$	30.29					$	29.75
Granted			$	44.17					$	44.17
Vested			$	—					$	—
Forfeited			$	30.01					$	—
Unvested balance, end of year			$	34.42					$	33.48

Share based compensation expense

The following tables present pre-tax and after-tax share-based compensation expense recognized as well as the unrecognized compensation cost associated with unvested awards and the weighted average period over which it is expected to be recognized.

			Year Ended December 31,
			2020						2019						2018
Pre-Tax
Stock options and SARs			$	11,744					$	12,866					$	16,272
Restricted share and unit awards			41,284						38,988						34,025
Performance awards			14,729						8,949						4,414
ESPP			2,135						3,045						1,224
Total			$	69,892					$	63,848					$	55,935
After-Tax
Stock options and SARs			$	10,388					$	11,450					$	14,894
Restricted share and unit awards			34,599						32,999						29,044
Performance awards			13,380						8,295						4,127
ESPP			1,978						2,758						1,114
Total			$	60,345					$	55,502					$	49,179

Unrecognized compensation cost

			December 31, 2020
			Stock Options and SARs						Restricted Common Shares and Units						Performance Common Shares and Units
Unrecognized compensation cost related to unvested awards			$	9,333					$	52,726					$	9,450
Weighted average recognition period (years)			1.02						1.48						0.66

Restricted Common Shares And Restricted Units

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Weighted average grant date fair value of restricted stock

The following table presents the weighted average grant date fair value of restricted shares and restricted unit awards granted and the aggregate fair value of restricted shares and unit awards vesting in each year.

			Year Ended December 31,
			2020						2019						2018
Restricted shares and restricted unit awards granted			1,535,330						1,195,741						1,563,287
Weighted average grant date fair value			$	37.55					$	32.89					$	26.86
Aggregate fair value of vested restricted share and unit awards			$	39,703					$	46,262					$	39,898

Performance Common Shares and Units

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Weighted average grant date fair value of restricted stock

The following table presents the weighted average grant date fair values of performance awards granted.

			Year Ended December 31,
			2020						2019						2018
Performance awards			557,204						696,360						743,513
Weighted average grant date fair value			$	44.17					$	36.05					$	24.77

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