DISCLOSURES REGARDING FAIR VALUES OF FINANCIAL INSTRUMENTS, Securities in Unrealized Loss Position (Details) - USD ($) $ in Thousands |
9 Months Ended | 12 Months Ended |
|---|---|---|
Sep. 30, 2016 |
Dec. 31, 2015 |
|
| Securities in an unrealized loss position, fair value [Abstract] | ||
| One year or greater | $ 813,179 | $ 597,652 |
| Less than one year | 1,114,807 | 4,468,844 |
| Fair Value, Total | 1,927,986 | 5,066,496 |
| Securities in an unrealized loss position, aggregate loss [Abstract] | ||
| One year or greater | 4,923 | 4,259 |
| Less than one year | 2,558 | 19,711 |
| Unrealized Losses, Total | $ 7,481 | $ 23,970 |