Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Property and equipment
Accumulated depreciation	$ 46,543	$ 42,479
Stockholders' Equity
Common Shares, par value (in dollars per share)	$ 0.015	$ 0.015
Common Shares, authorized	233,333,000	233,333,000
Common Shares, issued	93,105,000	92,650,000
Common Shares, outstanding	93,105,000	92,650,000
Investments available for sale
Amortized Cost	$ 1,629,538	$ 1,275,972
Fixed maturities
Investments available for sale
Amortized Cost	1,497,186	1,189,978
Short-term investments
Investments available for sale
Amortized Cost	$ 132,352	$ 85,994