Investment in Available-for-Sale Securities (Tables)

6 Months Ended

Jun. 30, 2013

Available-For-Sale Securities [Abstract]

Schedule of Available-for-sale Securities Reconciliation [Table Text Block]

The following is a summary of the Company’s investment in available-for-sale securities as of June 30, 2013: 

	Cost		Unrealized Gains		Unrealized Losses		Fair Value
U.S. federal agency securities	$	49,608	$	56	$	(629)	$	49,035
Municipal securities		844,796		1,873		(552)		846,117
Certificates of deposit		1,542,914		8,482		(30,014)		1,521,382
Corporate debt securities		187,645		438		(8,545)		179,538
	$	2,624,963	$	10,849	$	(39,740)	$	2,596,072

The following is a summary of the Company’s investment in available-for-sale securities as of December 31, 2012:

	Cost		Unrealized Gains		Unrealized Losses		Fair Value
U.S. federal agency securities	$	19,592	$	196	$	-	$	19,788
Municipal securities		1,154,841		2,882		(2,090)		1,155,633
Certificates of deposit		1,193,494		8,734		(16,904)		1,185,324
Corporate debt securities		285,524		4,164		(9,633)		280,055
Equity securities – ClearSign common stock		7,905		9,485		-		17,390
	$	2,661,356	$	25,461	$	(28,627)	$	2,658,190

Available-for-sale Securities [Table Text Block]

The cost and fair value of investments in available-for-sale securities, by contractual maturity, as of June 30, 2013, were as follows:

	Cost		Fair Value
Due within one year	$	798,269	$	776,053
Due after one year through three years		751,955		752,081
Due after three years		1,074,739		1,067,938
	$	2,624,963	$	2,596,072