Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2017

Schedule of nonvested restricted stock and deferred shares activity and related information

	Year Ended December 31,
	2017			2016			2015
		Weighted			Weighted			Weighted
		Average			Average			Average
		Grant Date			Grant Date			Grant Date
	Shares	Fair Value		Shares	Fair Value		Shares	Fair Value
	(Shares in thousands)
Unvested at beginning of year	210	$	53.79	244	$	52.61	214	$	53.74
Granted	139		60.88	140		56.33	180		50.87
Cancelled/Forfeitures	(9)		55.55	(42)		54.43	(28)		53.99
Vested	(123)		55.35	(132)		53.10	(122)		51.72
Unvested at end of year	217	$	57.31	210	$	53.79	244	$	52.61

Schedule of stock-based compensation fair value assumptions

	Year Ended
	December 31,
	2017		2016		2015
Expected life (years)	3.0		3.0		3.0
Expected stock price volatility	25.0	%	24.8	%	23.4	%
Expected dividend yield	1.2	%	1.3	%	1.2	%
Risk-free interest rate	1.5	%	0.9	%	1.1	%

Schedule of stock option activity and related information

	Year Ended December 31,
	2017					2016			2015
		Weighted		Weighted			Weighted			Weighted
		Average		Average			Average			Average
		Exercise		Intrinsic			Exercise			Exercise
	Options	Price		Value		Options	Price		Options	Price
	(Options in thousands)
Outstanding at beginning of year	130	$	54.46			362	$	48.46	495	$	47.34
Granted	—		—			—		—	—		—
Cancelled/Forfeitures	(3)		55.81			(43)		52.93	(69)		51.66
Exercised	(32)		53.19			(189)		43.31	(64)		36.29
Outstanding at end of year	95	$	54.91	$	21.04	130	$	54.46	362	$	48.46
Exercisable at end of year	93	$	54.85	$	21.10	82	$	53.38	192	$	45.10

Schedule of information about options outstanding

The following table summarizes information about options outstanding at December 31, 2017:

	Options Outstanding				Options Exercisable
		Weighted Average	Weighted Average			Weighted Average
	Number	Remaining Contractual	Exercise		Number	Exercise
Range of Exercise Prices	Outstanding	Life (years)	Price		Exercisable	Price
	(Options in thousands)
$29.05-$37.41	7,150	4.45	$	36.24	7,150	$	36.24
$54.76–$54.76	39,781	5.59		54.76	39,781		54.76
$57.47–$60.10	47,613	6.35		57.84	46,411		57.78
	94,544	5.88	$	54.91	93,342	$	54.85

Schedule of the Company's RSU activity and related information

	Year Ended December 31,
	2017				2016				2015
		Weighted		Weighted			Weighted			Weighted
		Average		Average			Average			Average
		Purchase		Intrinsic			Purchase			Purchase
	RSUs	Price		Value	RSUs		Price		RSUs	Price
	(RSU’s in thousands)
Outstanding at beginning of year	148	$	36.37			101	$	36.14	80	$	32.08
Granted	47		49.92			89		35.41	60		37.13
Cancelled/Forfeitures	(3)		41.55			(28)		32.25	(9)		36.92
Settled	(18)		39.09			(14)		36.91	(30)		27.10
Outstanding at end of year	174	$	39.68	36.27	$	148	$	36.37	101	$	36.14
Vested at end of year	57	$	36.26	39.69	$	28	$	37.78	25	$	33.35

Restricted stock and deferred shares

Schedule of information about RSUs outstanding

The following table summarizes information about RSUs outstanding at December 31, 2017:

	RSUs Outstanding			RSUs Vested
		Weighted Average			Weighted Average
	Number	Purchase		Number	Purchase
Range of Purchase Prices	Outstanding	Price		Vested	Price
	(RSUs in thousands)
$31.63-$35.41	85	$	35.37	28	$	35.30
$37.13–$49.92	89		43.75	29		37.21
	174	$	39.68	57	$	36.26

Performance stock units

Schedule of unvested performance shares activity and related information

	Year Ended December 31,
	2017			2016			2015
		Weighted			Weighted			Weighted
		Average			Average			Average
		GrantDate			Grant Date			Grant Date
	Shares	Fair Value		Shares	Fair Value		Shares	Fair Value
	(Shares in thousands)
Unvested at beginning of year	267	$	56.96	201	$	57.98	107	$	56.97
Granted	98		60.45	107		55.27	106		58.94
Cancelled/Forfeitures	(38)		57.12	(41)		57.56	(12)		57.51
Vested	(54)		56.81	—		—	—		—
Unvested at end of year	273	$	58.23	267	$	56.96	201	$	57.98