Net Income Per Common Share (Tables)

3 Months Ended

Mar. 31, 2017

Earnings Per Share [Abstract]

Basic and Diluted Net Income Per Common Share Based on Weighted-average Shares Outstanding

Basic and diluted net income per common share based on weighted-average shares outstanding are calculated as follows:

	Income (Numerator)		Shares (Denominator)		Per Share Amount
	(Dollars in thousands, except per share data)
Three Months Ended March 31, 2017
Basic
Income available to common stockholders	$	22,050		15,864,807	$	1.39
Dilutive effect of stock options		—		373,191
Diluted
Income available to common stockholders plus assumed    exercises of stock options	$	22,050		16,237,998	$	1.36
Three Months Ended March 31, 2016
Basic
Income available to common stockholders	$	16,579		15,534,416	$	1.07
Dilutive effect of stock options		—		281,955
Diluted
Income available to common stockholders plus assumed    exercises of stock options	$	16,579		15,816,371	$	1.05

Average Exercise Price of Options Excluded from Computation of Diluted Net Income Per Common Share

The following table shows the number and average exercise price of options that were excluded from the computation of diluted net income per common share for each period because the options’ exercise prices were greater than the average market price of the common shares:

	Shares		Average ExercisePrice
Three Months Ended March 31, 2017		—	$	—
Three Months Ended March 31, 2016		236,451	$	58.59