Employee Benefits (Tables)

12 Months Ended

Dec. 31, 2017

Share Based Compensation Arrangement By Share Based Payment Award [Line Items]

Total Expense Recorded for Stock Based Compensation

The following table presents the total stock-based compensation expense recorded and the total income tax benefit recognized for stock-based compensation arrangements for the years indicated (in thousands):

	For the years ended December 31,
	2017		2016		2015
Service condition restricted stock expense	$	10,334	$	10,377	$	9,439
Performance-based restricted stock expense	5,387		4,927		7,403
Restricted stock expense under the Plan	15,721		15,304		16,842
Canadian Plan restricted stock expense	709		650		732
Total stock-based compensation expense	$	16,430	$	15,954	$	17,574
Total income tax benefit recognized related to stock-based compensation	$	6,168	$	4,749	$	6,217

Profit Sharing and 401(k) Contributions for the Periods

The following table displays our profit-sharing and retirement plan contributions for the periods presented (in thousands):

	Years ended December 31,
	2017		2016		2015
Profit-sharing contributions	$	1,613	$	1,001	$	965
Retirement plan matching contributions	1,602		1,518		1,319

Restricted Stock Subject Only to a Service Condition

Share Based Compensation Arrangement By Share Based Payment Award [Line Items]

Status and Changes in Restricted Stock Grants that Subject to Service Condition

The following table details the status and changes in our restricted stock grants that are subject only to a service condition for the year ended December 31, 2017:

	Number of Shares		Weighted Average Grant Date Fair Value
Non-vested, January 1, 2017	607,501		$	54.67
Granted	143,460		61.20
Vested	(187,295	)	57.47
Forfeited	(44,291	)	54.99
Non-vested, December 31, 2017	519,375		$	55.44

Weighted-Average Grant Date Fair Value for Shares Granted and the Total Fair Value of Shares Vested

The following table shows the weighted-average grant date fair value for shares granted and the total fair value of shares vested during the years indicated:

	Years ended December 31,
	2017		2016		2015
Weighted-average grant date fair value	$	61.20	$	47.97	$	61.42
Fair value of shares vested (in thousands)	$	10,764	$	9,497	$	7,797

Restricted Shares Subject to Service and Performance Conditions

Share Based Compensation Arrangement By Share Based Payment Award [Line Items]

Status and Changes in Restricted Stock Grants that Subject to Service Condition

The following table details the status and changes in our restricted stock grants subject to service and performance conditions for the year ended December 31, 2017:

	Number of Shares		Weighted Average Grant Date Fair Value
Non-vested, January 1, 2017	153,620		$	55.90
Granted	160,340		54.86
Vested	(102,367	)	56.58
Forfeited	(45,675	)	55.86
Non-vested, December 31, 2017	165,918		$	55.85

Weighted-Average Grant Date Fair Value for Shares Granted and the Total Fair Value of Shares Vested

The following table shows the weighted-average grant date fair value for shares granted and the total fair value of shares vested during the years indicated:

	Years ended December 31,
	2017		2016		2015
Weighted-average grant date fair value	$	54.86	$	55.90	$	61.29
Fair value of shares vested (in thousands)	$	5,792	$	6,209	$	5,936