SCHEDULE II - Valuation and Qualifying Accounts (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Allowance for Uncollectible Accounts
Changes in valuation and qualifying accounts
Balance at Beginning of Year	$ 157,000	$ 122,000
Additions Charged to Costs and Expenses	41,000	62,000
Deductions	(60,000)	(27,000)
Balance at End of Year	138,000	157,000
Inventory Reserves
Changes in valuation and qualifying accounts
Balance at Beginning of Year	1,474,000	1,110,000
Additions Charged to Costs and Expenses	718,000	1,191,000
Deductions	(1,092,000)	(827,000)
Balance at End of Year	$ 1,100,000	$ 1,474,000