CAPITAL STOCK AND STOCK AWARD PLANS (Tables)

12 Months Ended

Dec. 31, 2016

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

Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs

A summary of our total compensation expense recognized in our consolidated statements of operations and comprehensive income for stock-based compensation is as follows (in thousands):

	2016		2015		2014
Stock options	$	9,178	$	14,607	$	9,243
Stock awards	25,912		40,785		36,510
Company expense on ESPP discount	2,475		2,269		2,108
Total stock-based compensation expense	$	37,565	$	57,661	$	47,861

Schedule of Share-based Compensation, Stock Options, Activity

The following schedule summarizes stock option activity in the plans. All outstanding unvested options as of December 31, 2016, relate to the performance-based grants from 2011 through 2016.

	Options		Weighted Average Exercise Price		Aggregate Intrinsic Value (in thousands)		Average Remaining Life (years)
Outstanding at December 31, 2015	6,150,861		$	65.03	$	—	8.1
Grants	1,250,154		76.72
Exercised	(86,840	)	61.82
Terminated	(306,252	)	68.81
Outstanding at December 31, 2016	7,007,923		$	67.00	$	43,875	7.7
Vested at December 31, 2016	2,646,205		$	64.63			6.7
Exercisable at December 31, 2016	2,646,205		$	64.63			6.7

Schedule of Intrinsic Value of Options Exercised

Information on the intrinsic value of options exercised is as follows (in thousands):

2016	$	981
2015	400
2014	4

Schedule of Share-based Compensation, Activity

The following table summarizes these unvested stock option grants as of December 31, 2016:

Year of Grant	First Vesting Date	Last Vesting Date	Options Granted, Net of Forfeitures	Weighted Average Grant Date Fair Value		Unvested Options
2015	December 31, 2016	December 31, 2020	1,428,531	$	12.66	1,142,825
2016	December 31, 2017	December 31, 2021	1,250,154	12.60		1,250,154
			2,678,685	$	12.63	2,392,979

The following table summarizes performance-based options by year of grant:

Year of Grant	First Vesting Date	Last Vesting Date	Options Granted, Net of Forfeitures	Weighted Average Grant Date Fair Value		Unvested Options
2012	December 31, 2013	December 31, 2017	1,149,441	$	13.15	666,676
2013	December 31, 2014	December 31, 2018	1,425,529	11.83		541,701
2014	December 31, 2015	December 31, 2019	1,277,409	14.17		804,595
			3,852,379	$	13.00	2,012,972

The following table summarizes performance shares and restricted stock units by year of grant:

Year of grant	First vesting date	Last vesting date	Performance Shares and Stock Units Granted, Net of Forfeitures	Weighted Average Grant Date Fair Value (1)		Unvested Performance Shares and Restricted Stock Units
2012	December 31, 2013	December 31, 2017	325,536	$	48.65	188,811
2013	December 31, 2014	December 31, 2018	394,672	46.50		149,975
2014	December 31, 2015	December 31, 2019	336,683	60.57		212,110
2015	December 31, 2016	December 31, 2020	390,163	51.88		343,342
2016	December 31, 2017	December 31, 2021	350,937	64.91		350,937
			1,797,991	$	54.29	1,245,175

________________________ 

(1) Amount shown is the weighted average grant date fair value of performance shares and restricted stock units granted, net of forfeitures.

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions

The fair value per option was estimated using the Black-Scholes option pricing model with the following assumptions:

	2016 Grants		2015 Grants		2014 Grants
Risk-free interest rate	2.13-2.14%		1.95-1.96%		1.93-1.96%
Dividend per share (quarterly amounts)	$0.43-0.45		$0.38-0.43		$0.35-0.38
Expected volatility factor	20.0-21.5%		22.0-24.0%		22.0-25.0%
Expected option term	6.26 years		6.29 years		6.3 years
Weighted average fair value per option	$	12.60	$	12.68	$	14.23

Schedule of Nonvested Restricted Stock Units Activity

The following table summarizes our unvested performance shares and restricted stock unit grants as of December 31, 2016:

	Number of Performance Shares and Restricted Stock Units		Weighted Average Grant Date Fair Value
Unvested at December 31, 2015	1,272,040		$	52.56
Granted	350,937		64.91
Vested	(175,413	)	52.40
Forfeitures	(202,389	)	53.61
Unvested at December 31, 2016	1,245,175		$	55.90

Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity

The following table summarizes these unvested restricted share and restricted stock unit grants as of December 31, 2016:

	Number of Restricted Shares and Stock Units		Weighted Average Grant Date Fair Value
Unvested at December 31, 2015	1,127,522		$	52.69
Granted	464,823		63.02
Vested	(291,525	)	52.01
Forfeitures	(60,664	)	53.06
Unvested at December 31, 2016	1,240,156		$	56.70

Schedule Of Fair Value Stock Awards Vested

A summary of the fair value of full value awards vested (in thousands):

2016	$	25,912
2015	40,785
2014	36,510

Schedule of Share-based Compensation, Employee Stock Purchase Plan, Activity

The following is a summary of the employee stock purchase plan activity (dollar amounts in thousands):

	Shares Purchased By Employees	Aggregate Cost to Employees		Expense Recognized By the Company
2016	225,241	$	14,032	$	2,475
2015	228,103	13,045		2,269
2014	231,564	11,943		2,108

Share Repurchase Program Disclosure

The activity under this authorization is as follows (dollar amounts in thousands):

	Shares Repurchased	Total Value of Shares Repurchased
2013 Program
2013 Purchases	930,075	$	57,689
2014 Purchases	3,763,583	239,037
2015 Purchases	3,420,681	232,113
2016 Purchases	2,467,097	176,676