Investments and Fair Value Measurements (Details) - USD ($) $ in Thousands		Jun. 30, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		$ 64,302	$ 59,520
Unrealized Losses		(340)	(18)
Aggregate Fair Value		63,962	59,502
Financial assets [Abstract]
Municipal securities	[1]	63,962	59,502
Foreign currency exchange contracts		2	14
Total financial assets		63,964	59,516
Financial liabilities [Abstract]
Foreign currency exchange contracts		326	1,359
Total financial liabilities		326	1,359
Short Term Municipal Securities Funds [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	[2]	64,302	59,520
Unrealized Losses	[2]	(340)	(18)
Aggregate Fair Value	[2]	63,962	59,502
Level 1 [Member]
Financial assets [Abstract]
Municipal securities	[1]	63,962	59,502
Foreign currency exchange contracts		0	0
Total financial assets		63,962	59,502
Financial liabilities [Abstract]
Foreign currency exchange contracts		0	0
Total financial liabilities		0	0
Level 2 [Member]
Financial assets [Abstract]
Municipal securities	[1]	0	0
Foreign currency exchange contracts		2	14
Total financial assets		2	14
Financial liabilities [Abstract]
Foreign currency exchange contracts		326	1,359
Total financial liabilities		326	1,359
Level 3 [Member]
Financial assets [Abstract]
Municipal securities	[1]	0	0
Foreign currency exchange contracts		0	0
Total financial assets		0	0
Financial liabilities [Abstract]
Foreign currency exchange contracts		0	0
Total financial liabilities		$ 0	$ 0

[1] At June 30, 2015 and December 31, 2014, municipal securities consisted solely of holdings in short-term municipal security funds.

[2] Do not have a set maturity date.