Marketable Securities (Tables)

9 Months Ended

Sep. 30, 2016

Investments, Debt and Equity Securities [Abstract]

Summary of available-for-sale securities

The following is a summary of available-for-sale securities at:

($ in thousands)		September 30, 2016				December 31, 2015
Marketable Securities:	Fair Value Hierarchy	Cost		Estimated Fair Value		Cost		Estimated Fair Value
Certificates of deposit
with unrecognized losses for less than 12 months		$	40	$	39	$	4,810	$	4,797
with unrecognized losses for more than 12 months		—		—		239		238
with unrecognized gains		5,969		5,995		2,800		2,805
Total Certificates of deposit	Level 1	6,009		6,034		7,849		7,840
US Treasury and agency notes
with unrecognized losses for less than 12 months		—		—		860		857
with unrecognized losses for more than 12 months		—		—		—		—
with unrecognized gains		1,935		1,941		736		738
Total US Treasury and agency notes	Level 2	1,935		1,941		1,596		1,595
Corporate notes
with unrecognized losses for less than 12 months		5,595		5,575		14,638		14,516
with unrecognized losses for more than 12 months		1,461		1,439		2,080		2,061
with unrecognized gains		9,591		9,629		3,334		3,339
Total Corporate notes	Level 2	16,647		16,643		20,052		19,916
Municipal notes
with unrecognized losses for less than 12 months		811		802		1,742		1,725
with unrecognized losses for more than 12 months		360		356		301		298
with unrecognized gains		1,831		1,841		1,435		1,441
Total Municipal notes	Level 2	3,002		2,999		3,478		3,464
		$	27,593	$	27,617	$	32,975	$	32,815

Summary of maturities, at par, of marketable securities by year

The following tables summarize the maturities, at par, of marketable securities as of:

	September 30, 2016
($ in thousands)	2016		2017		2018		2019		Total
Certificates of deposit	$	879	$	531	$	4,400	$	169	$	5,979
U.S. Treasury and agency notes	—		1,234		579		138		1,951
Corporate notes	—		5,207		7,723		3,240		16,170
Municipal notes	—		840		1,705		415		2,960
	$	879	$	7,812	$	14,407	$	3,962	$	27,060

	December 31, 2015
($ in thousands)	2016		2017		2018		2019		Total
Certificates of deposit	$	2,492	$	631	$	4,510	169		$	7,802
U.S. Treasury and agency notes	100		759		579		188		1,626
Corporate notes	4,572		6,525		6,462		1,881		19,440
Municipal notes	995		940		1,455		—		3,390
	$	8,159	$	8,855	$	13,006	$	2,238	$	32,258