Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2015

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

Schedule of assumptions used in estimating fair value of stock options using Black-Scholes option pricing model

In determining the estimated fair value of our stock options as of the date of grant, we used the Black-Scholes option pricing model with the following assumptions:

	2015		2014		2013
Risk-free interest rate	1.02 - 1.38%		1.3 - 1.4%		0.59 - 0.63%
Dividend yield	5.00	%	5.00	%	5.00	%
Volatility factors of the expected market price for our common stock	19.0 - 20.0%		17.8 - 18.0%		24.2 - 31.7%
Weighted average expected life of options	4.0 years		4.17 years		4.25 - 7.0 years

Summary of stock option activity

The following is a summary of stock option activity in 2015:

	Shares	Weighted Average Exercise Price		Weighted Average Remaining Contractual Life (years)	Intrinsic Value ($000’s)
Outstanding as of December 31, 2014	2,460,628	$	57.45
Options granted in 2015 pre-spin	792,434	76.62
Options exercised in 2015 pre-spin	130,273	43.30
Options forfeited in 2015 pre-spin	12,058	62.47
Options expired in 2015 pre-spin	2,802	66.43
Options outstanding pre-spin	3,107,929	62.90
Options forfeited/expired at spin	511,832	65.51
Options issued at spin	488,360	52.51
Options outstanding post-spin	3,084,457	52.51
Options granted in 2015 post-spin	—	0.00
Options exercised in 2015 post-spin	20,814	35.13
Options forfeited in 2015 post-spin	11,914	55.67
Options expired in 2015 post-spin	—	0.00
Outstanding as of December 31, 2015	3,051,729	52.62		7.03	$	18,216
Exercisable as of December 31, 2015	2,183,113	$	49.73	6.36	$	16,815

Summary of status of nonvested restricted stock and restricted stock units and changes during the year

A summary of the status of our non-vested restricted stock and restricted stock units as of December 31, 2015, and changes during the year ended December 31, 2015 follows:

	Restricted Stock	Weighted Average Grant Date Fair Value		Restricted Stock Units	Weighted Average Grant Date Fair Value
Nonvested at December 31, 2014	402,741	$	58.51	11,392	$	58.79
Granted in 2015 pre-spin	190,429	75.46		7,252	71.70
Vested in 2015 pre-spin	237,461	61.69		6,856	59.79
Forfeited in 2015 pre-spin	5,602	61.12		0	0.00
Non-vested post-spin	350,107	65.53		11,788	66.15
Forfeited at spin	61,166	64.94		0	0.00
Granted at spin	54,364	2.34		2,216	2.34
Non-vested post-spin	343,305	57.60		14,004	58.02
Granted in 2015 post-spin	31,176	56.12		0	0.00
Vested in 2015 post-spin	3,323	50.49		0	0.00
Forfeited in 2015 post-spin	8,065	52.57		0	0.00
Nonvested at December 31, 2015	363,093	$	57.65	25,500	$	58.02