Employee Benefits - Equity Incentive Plans (Details) $ in Thousands				3 Months Ended		6 Months Ended
	Jun. 30, 2010 shares	May 18, 2007 shares	Jun. 21, 2006 shares	Jun. 30, 2017 USD ($) item shares	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($) item shares	Jun. 30, 2016 USD ($)	Dec. 31, 2016 shares	Jul. 28, 2014 shares
Employee Benefits
Number of stock option plans frozen | item				2		2
Share-based Compensation | $						$ 1,059	$ 509
Percentage of participant's contribution matched by Company						100.00%
Company contributions | $				$ 348	$ 325	$ 704	651
Restricted Stock Units (RSUs)
Employee Benefits
Units outstanding				306,250		306,250
Total stock-based compensation expense | $				$ 196	190	$ 406	402
Employee And Directors Time Based Options
Employee Benefits
Options outstanding								377,015
Employee And Directors Performance Options
Employee Benefits
Options outstanding								1,020,242
Stock Appreciation Rights (SARs)
Employee Benefits
Total stock-based compensation expense | $						$ 357
Allocated share based compensation expense reversal | $					$ 90		$ 112
2014 Plan
Employee Benefits
Options outstanding				427,000		427,000		389,500
2014 Plan | Restricted Stock Units (RSUs)
Employee Benefits
Number of units granted						275,000
Units outstanding								288,500
2010 Option Plan | Employee And Directors Stock Options
Employee Benefits
Number of shares or units authorized for grants	2,239,906
Vesting period	4 years
2010 Option Plan | Employee And Directors Time Based Options
Employee Benefits
Options outstanding				369,410		369,410
2010 Option Plan | Employee And Directors Performance Options
Employee Benefits
Options outstanding				994,385		994,385
2010 Option Plan | Employee And Directors Super Performance Options
Employee Benefits
Options outstanding				308,526		308,526		316,550
2006 Option Plan
Employee Benefits
Number of shares or units authorized for grants			450,000
Options outstanding				87,500		87,500		127,500
Vesting period			4 years
Term of awards			10 years
SAR Plan
Employee Benefits
Number of shares or units authorized for grants		200,000
Units outstanding				73,000		73,000		93,000
Term of awards		10 years
Allocated share based compensation expense reversal | $				$ 169
2014 Option Plan
Employee Benefits
Number of shares or units authorized for grants									1,273,838
Maximum
Employee Benefits
Percentage of participant's salary matched by Company						6.00%