Commitments, Contingencies, and Concentrations (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Commitments, Contingencies, and Concentrations [Abstract]
Percentage of employees involved in bargaining agreement (in hundredths)	17.00%
Agreement expiration date	Mar. 31, 2015
Rental expense	$ 2,926,000	$ 2,214,000	$ 1,853,000
Future minimum operating lease rental obligations [Abstract]
2014	2,583,000
2015	2,380,000
2016	1,577,000
2017	1,390,000
2018	809,000
Thereafter	2,441,000
Total	$ 11,180,000