Investment Securities (Tables) - USD ($)
$ in Thousands

3 Months Ended

Mar. 31, 2016

Dec. 31, 2015

Investments, Debt and Equity Securities [Abstract]

Available-for-sale Securities [Table Text Block]

The investment securities consist of the following at March 31, 2016 and December 31, 2015 (in thousands):

	March 31, 2016		December 31, 2015
Federal and municipal tax-exempt debt securities	$	7,226	$	4,951
Corporate bonds	21,410		25,400
U.S. Treasury securities	6,018		7,537
Commercial paper	700		2,097
Certificates of deposit	997		1,248
Total investment securities	$	36,351	$	41,233

Schedule of Available-for-sale Securities [Line Items]

Investment Maturity Date Range Start

2016

Investment Maturity Date Range End

2039

Investment securities

$ 36,351

$ 41,233

^[1]

Federal tax-exempt debt securities [Member]

Schedule of Available-for-sale Securities [Line Items]

Investment securities

7,226

4,951

Corporate Bond Securities [Member]

Schedule of Available-for-sale Securities [Line Items]

Investment securities

21,410

25,400

US Treasury Securities [Member]

Schedule of Available-for-sale Securities [Line Items]

Investment securities

6,018

7,537

Commercial Paper [Member]

Schedule of Available-for-sale Securities [Line Items]

Investment securities

700

2,097

Certificates of deposit [Member]

Schedule of Available-for-sale Securities [Line Items]

Investment securities

$ 997

$ 1,248

[1] December 31, 2015 balances were derived from audited consolidated financial statements.