Marketable Securities - Amortized Cost and Estimated Fair Value of Marketable Securities (Details) - USD ($) $ in Thousands |
Dec. 31, 2016 |
Dec. 31, 2015 |
---|---|---|
Securities Investments | ||
Cost | $ 68,527 | $ 46,158 |
Gross Unrealized Gains | 1,931 | 259 |
Gross Unrealized Losses | 3,971 | 2,630 |
Fair Value | 66,487 | 43,787 |
Securities Investments [Member] | ||
Securities Investments | ||
Cost | 6,470 | 6,463 |
Gross Unrealized Gains | 0 | 10 |
Gross Unrealized Losses | 3,945 | 2,523 |
Fair Value | 2,525 | 3,950 |
Debt Securities Carried by EGL [Member] | ||
Securities Investments | ||
Cost | 38,392 | 37,404 |
Gross Unrealized Gains | 77 | 94 |
Gross Unrealized Losses | 15 | 8 |
Fair Value | 38,454 | 37,490 |
Investment Funds [Member] | ||
Securities Investments | ||
Cost | 23,665 | 2,291 |
Gross Unrealized Gains | 1,854 | 155 |
Gross Unrealized Losses | 11 | 99 |
Fair Value | $ 25,508 | $ 2,347 |