Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2016

Accounting Policies [Abstract]

Computation of Basic EPS to Dilutive EPS

The following table reconciles the computation of basic EPS to dilutive EPS:

	Net Earnings (in thousands)		Weighted Average Shares		Per Share Amount
For the year ended December 31, 2016:
Net earnings per share, basic	$	104,774		66,013,004	$	1.59
Effect of stock options and stock grants		—		89,882		—
Net earnings per share, assuming dilution	$	104,774		66,102,886	$	1.59
For the year ended December 31, 2015:
Net earnings per share, basic	$	100,381		64,892,934	$	1.55
Effect of stock options and stock grants		—		175,096		(0.01	)
Net earnings per share, assuming dilution	$	100,381		65,068,030	$	1.54
For the year ended December 31, 2014:
Net earnings per share, basic	$	89,559		64,047,803	$	1.40
Effect of stock options		—		260,732		(0.01	)
Net earnings per share, assuming dilution	$	89,559		64,308,535	$	1.39