Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2012

Significant Accounting Policies [Abstract]

Summary Of Securities

	Current						Noncurrent
	2012			2011			2012			2011
Aggregate fair value	$	8,416,447		$	5,094,703		$	4,282,664		$	4,755,809
Gross unrealized holding gains		(3,707	)		(4,929	)		(698	)		(12,995	)
Gross unrealized holding losses		—			857			1,405			1,192
Amortized cost basis		8,412,740			5,090,631			4,283,371			4,744,006
Accrued interest		15,067			17,676			12,086			15,066
Amounts shown on balance sheets	$	8,427,807		$	5,108,307		$	4,295,457		$	4,759,072