Common Stock (Tables)

6 Months Ended

Jun. 30, 2016

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

Stock Options Status and Activity

Stock Options — The following table reflects the status and activity for all options to purchase common stock for the period indicated:

	Six Months Ended June 30, 2016
	Shares Under Option		Weighted Avg. Exercise Prices		Weighted Avg. Remaining Life in Years	Aggregate Intrinsic Value
						(Millions)
Outstanding Stock Options
Outstanding, January 1, 2016	1,144,719		$	34.69	3.7	$	19
Exercised	(19,192	)	9.31			1
Outstanding, March 31, 2016	1,125,527		$	35.12	3.5	$	12
Forfeited	(788	)	51.88
Exercised	(183,774	)	23.07			5
Outstanding, June 30, 2016	940,965		$	37.46	3.1	$	14

Nonvested Restricted Shares

Restricted Stock — The following table reflects the status for all nonvested restricted shares for the period indicated:

	Six Months Ended June 30, 2016
	Shares		Weighted Avg. Grant Date Fair Value
Nonvested Restricted Shares
Nonvested balance at January 1, 2016	496,842		$	51.65
Granted	347,398		35.98
Vested	(156,109	)	46.50
Nonvested balance at March 31, 2016	688,131		$	44.90
Vested	(20,221	)	42.32
Forfeited	(32,192	)	53.91
Nonvested balance at June 30, 2016	635,718		$	44.42