Investments Amortized Cost and Estimated Fair Value (Details) - Steel Excel $ in Thousands	Jun. 30, 2015 USD ($)
Cost
Mature in one year or less	$ 0
Mature after one year through three years	0
Mature after three years	35,205
Total debt securities	35,205
Securities with no contractual maturities	116,235
Cost	151,440
Estimated Fair Value
Mature in one year or less	0
Mature after one year through three years	0
Mature after three years	34,298
Total debt securities	34,298
Securities with no contractual maturities	125,898
Fair value	$ 160,196