Employee Benefits (Tables)

12 Months Ended

Dec. 31, 2017

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Schedule of Compensation Cost for Share-based Payment Arrangements, Allocation of Share-based Compensation Costs by Plan [Table Text Block]

Share-based payments recorded in salaries and benefits expense are as follows:

	Year Ended December 31,
	2017		2016		2015
	(In thousands)
Stock option and ESPP expense	$	480	$	437	$	518
Nonvested share expense	7,794		6,293		5,723
Subtotal	8,274		6,730		6,241
Tax benefit	3,188		2,574		2,367
Stock-based compensation expense, net of tax benefit	$	5,086	$	4,156	$	3,874

Stock Options [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based Compensation, Stock Options, Activity [Table Text Block]

A summary of option activity under the 2009 Plan for the year ended December 31, 2017 is as follows:

	Shares	Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term in Years	Aggregate Intrinsic Value (in 000’s)
Outstanding at December 31, 2016	656,400	$	13.11
Granted	—	$	—
Exercised	109,400	$	8.21
Forfeited	12,798	$	28.85
Expired	115,547	$	29.73
Outstanding at December 31, 2017	418,655	$	9.32	1.81 years	$	2,795.0
Exercisable at December 31, 2017	418,655	$	9.32	1.81 years	$	2,795.0

Restricted Stock [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based Compensation, Stock Options, Activity [Table Text Block]

A summary of the Company’s nonvested shares as of December 31, 2017 and changes during the year ended December 31, 2017, including shares under both the 2009 Plan and the Inducement Plan, is as follows:

	Shares	Weighted- Average Grant-Date Fair Value
Nonvested at December 31, 2016	1,993,628	$	12.16
Granted	485,263	$	15.55
Vested	652,193	$	12.28
Forfeited	100,789	$	13.35
Nonvested at December 31, 2017	1,725,909	$	13.03