Fair Value Measurements - Schedule of Fair Value Assets and Liabilities Measured on Recurring Basis (Details) - Fair Value, Measurements, Recurring [Member] - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]
Investments, Fair Value Disclosure	$ 27,428	$ 26,365
Corporate Bonds And Notes [Member]
Schedule of Available-for-sale Securities [Line Items]
Investments, Fair Value Disclosure	20,460	20,744
Municipal Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Investments, Fair Value Disclosure	6,968	5,621
Fair Value, Inputs, Level 1 [Member]
Schedule of Available-for-sale Securities [Line Items]
Investments, Fair Value Disclosure
Fair Value, Inputs, Level 1 [Member] | Corporate Bonds And Notes [Member]
Schedule of Available-for-sale Securities [Line Items]
Investments, Fair Value Disclosure
Fair Value, Inputs, Level 1 [Member] | Municipal Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Investments, Fair Value Disclosure
Fair Value, Inputs, Level 2 [Member]
Schedule of Available-for-sale Securities [Line Items]
Investments, Fair Value Disclosure	27,428	26,365
Fair Value, Inputs, Level 2 [Member] | Corporate Bonds And Notes [Member]
Schedule of Available-for-sale Securities [Line Items]
Investments, Fair Value Disclosure	20,460	20,744
Fair Value, Inputs, Level 2 [Member] | Municipal Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Investments, Fair Value Disclosure	6,968	5,621
Fair Value, Inputs, Level 3 [Member]
Schedule of Available-for-sale Securities [Line Items]
Investments, Fair Value Disclosure
Fair Value, Inputs, Level 3 [Member] | Corporate Bonds And Notes [Member]
Schedule of Available-for-sale Securities [Line Items]
Investments, Fair Value Disclosure
Fair Value, Inputs, Level 3 [Member] | Municipal Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Investments, Fair Value Disclosure