Stock Compensation Plans (Tables)

12 Months Ended

Dec. 31, 2019

Share-based Payment Arrangement [Abstract]

Share-based Compensation Arrangements by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding [Table Text Block]

A summary of those awards granted in 2019 is presented below:

	Expected to be Settled in Equity	Expected to be Settled in Cash	Total Awards Granted
Performance-based restricted stock units	296,597	7,241	303,838
Time-based restricted stock units	157,465	3,940	161,405
Deferred shares	14,870	0	14,870

Summary of significant stock options granted

The fair value of stock option awards granted was estimated at the date of grant using a Black-Scholes option-pricing method with the following assumptions:

	2019			2018			2017
Weighted-average fair value per option	$	9.58		$	10.29		$	10.60
Risk-free interest rate	2.46		%	2.62		%	1.96		%
Dividend yield	2.52		%	2.30		%	2.96		%
Expected stock volatility	28.29		%	27.78		%	32.25		%
Expected life - years	5			5			5

Summary of stock option activity

A summary of stock option award activity for the year ended December 31, 2019 is presented below:

	Number of Shares		Weighted-average Exercise Price		Weighted-average Remaining Contractual Term	Aggregate Intrinsic Value (millions)
Outstanding - beginning of year	3,189,950		$	38.21
Granted - new awards	558,760		42.61
Exercised	(803,604	)	34.25
Canceled or expired	(31,834	)	42.36
Outstanding - end of year	2,913,272		$	40.10	6 years	$	47.2
Options expected to vest	2,913,272		$	40.10	6 years	$	47.2
Options exercisable	1,676,248		$	38.91	5 years	$	29.2

Summary of restricted share activity

A summary of stock award activity, including performance-based restricted stock units, time-based restricted stock units, deferred shares and restricted shares that will settle in common shares for the year ended December 31, 2019 is as follows:

	Number of Shares		Weighted-average Grant Date Fair Value
Outstanding - beginning of year	1,196,492		$	38.76
Granted - new awards	468,932		41.57
Vested	(539,396	)	32.08
Canceled or expired	(19,304	)	43.31
Outstanding - end of year	1,106,724		$	43.13