Investments (Tables)

12 Months Ended

Dec. 31, 2015

Investments, Debt and Equity Securities [Abstract]

Schedule of Held-To-Maturity Investments Estimated Fair Value of Investments

	Amortized  Cost		Gross  Unrealized  Losses		Estimated  Fair Value
2015
Certificates of deposit, commercial paper	$	6,690	$	5	$	6,685
2014
Certificates of deposit, commercial paper	$	10,699	$	2	$	10,697

Schedule of Maturities of Held-To-Maturity Investments

The maturities of held-to-maturity investments at December 31, 2015 and 2014, respectively were as follows (in thousands):

	Less than  1 Year		Total
2015
Certificates of deposit, commercial paper	$	6,690	$	6,690
2014
Certificates of deposit, commercial paper	$	10,699	$	10,699