Stock Compensation Plans (Tables)

12 Months Ended

Dec. 31, 2015

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Summary of significant stock options granted

The fair value of stock option awards granted during 2015, 2014 and 2013 was estimated at the date of grant using a Black-Scholes option-pricing method with the following assumptions:

	2015			2014			2013
Weighted-average fair value per option (Pre-Spinoff for 2014 and 2013)	$	11.67		$	23.09		$	21.17
Risk-free interest rate	1.58		%	1.64		%	1.09		%
Dividend yield	2.29		%	1.75		%	2.29		%
Expected stock volatility	36.53		%	50.96		%	50.66		%
Expected life - years	5			5			6

Summary of stock option activity

A summary of stock option award activity for the year ended December 31, 2015 is presented below:

	Number of Shares		Weighted-average Exercise Price		Weighted-average Remaining Contractual Term	Aggregate Intrinsic Value (millions)
Outstanding - beginning of year	3,168,363		$	33.57
Granted - new awards	491,615		41.56
Exercised	(297,765	)	22.35
Canceled or expired	(82,345	)	40.95
Outstanding - end of year	3,279,868		$	35.60	6 years	$	5.9
Options expected to vest	3,257,113		$	35.55	6 years	$	5.9
Options exercisable	2,034,395		$	32.41	5 years	$	5.9

Summary of restricted share activity

A summary of stock award activity, including restricted shares, deferred shares, performance-based restricted stock units and time-vested restricted stock units that will settle in common shares, for the year ended December 31, 2015 is as follows:

	Number of Shares		Weighted-average Grant Date Fair Value
Outstanding - beginning of year	687,030		$	39.61
Granted - new awards	485,975		41.39
Vested	(103,953	)	36.37
Canceled or expired	(54,282	)	41.44
Outstanding - end of year	1,014,770		$	40.69