Fair Values of Assets and Liabilities (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013 item	Dec. 31, 2012
Fair Values of Assets and Liabilities
Available for sale securities	$ 31,055	$ 23,500
Available for sale securities, current	19,150	12,920
Long term investments in available for sale securities	11,905	10,580
Amortized cost of available for sale securities	29,127	21,720
Unrealized gains on available for sale securities	2,185	2,050
Unrealized losses on available for sale securities	257	270
Number of available for sale securities in a loss position less than 12 months	36
Number of available for sale securities in a loss position 12 months or longer	0
Fair value of securities which is in loss position for less than 12 months	7,392
Gross proceeds from sale of available for sale securities	6,285	4,163
Gross realized gains recorded on sale of available for sale securities	329	63
Gross realized losses recorded on sale of available for sale securities	334	82
International bond fund
Fair Values of Assets and Liabilities
Unfunded commitment	0
High yield fund
Fair Values of Assets and Liabilities
Unfunded commitment	0
Total
Fair Values of Assets and Liabilities
Cash equivalents	14,866	22,149
Available for sale securities	31,054	23,500
Total	45,920	45,649
Total | Equity securities
Fair Values of Assets and Liabilities
Available for sale securities	8,247	7,284
Total | Financial services industry
Fair Values of Assets and Liabilities
Available for sale securities	3,668	6,025
Total | REIT industry
Fair Values of Assets and Liabilities
Available for sale securities	704	484
Total | Other
Fair Values of Assets and Liabilities
Available for sale securities	3,875	775
Total | Debt securities
Fair Values of Assets and Liabilities
Available for sale securities	22,807	16,216
Total | International bond fund
Fair Values of Assets and Liabilities
Available for sale securities	2,329	2,345
Total | High yield fund
Fair Values of Assets and Liabilities
Available for sale securities	2,309	2,168
Total | Industrial bonds
Fair Values of Assets and Liabilities
Available for sale securities	5,234	5,186
Total | Government bonds
Fair Values of Assets and Liabilities
Available for sale securities	7,075	4,666
Total | Financial bonds
Fair Values of Assets and Liabilities
Available for sale securities	1,154	982
Total | Other
Fair Values of Assets and Liabilities
Available for sale securities	4,706	869
Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Values of Assets and Liabilities
Cash equivalents	14,866	22,149
Available for sale securities	12,805	11,950
Total	27,671	34,099
Quoted Prices in Active Markets for Identical Assets (Level 1) | Equity securities
Fair Values of Assets and Liabilities
Available for sale securities	8,247	7,284
Quoted Prices in Active Markets for Identical Assets (Level 1) | Financial services industry
Fair Values of Assets and Liabilities
Available for sale securities	3,668	6,025
Quoted Prices in Active Markets for Identical Assets (Level 1) | REIT industry
Fair Values of Assets and Liabilities
Available for sale securities	704	484
Quoted Prices in Active Markets for Identical Assets (Level 1) | Other
Fair Values of Assets and Liabilities
Available for sale securities	3,875	775
Quoted Prices in Active Markets for Identical Assets (Level 1) | Debt securities
Fair Values of Assets and Liabilities
Available for sale securities	4,558	4,666
Quoted Prices in Active Markets for Identical Assets (Level 1) | Government bonds
Fair Values of Assets and Liabilities
Available for sale securities	4,558	4,666
Significant Other Observable Inputs (Level 2)
Fair Values of Assets and Liabilities
Available for sale securities	18,249	11,550
Total	18,249	11,550
Significant Other Observable Inputs (Level 2) | Debt securities
Fair Values of Assets and Liabilities
Available for sale securities	18,249	11,550
Significant Other Observable Inputs (Level 2) | International bond fund
Fair Values of Assets and Liabilities
Available for sale securities	2,329	2,345
Significant Other Observable Inputs (Level 2) | High yield fund
Fair Values of Assets and Liabilities
Available for sale securities	2,309	2,168
Significant Other Observable Inputs (Level 2) | Industrial bonds
Fair Values of Assets and Liabilities
Available for sale securities	5,234	5,186
Significant Other Observable Inputs (Level 2) | Government bonds
Fair Values of Assets and Liabilities
Available for sale securities	2,517
Significant Other Observable Inputs (Level 2) | Financial bonds
Fair Values of Assets and Liabilities
Available for sale securities	1,154	982
Significant Other Observable Inputs (Level 2) | Other
Fair Values of Assets and Liabilities
Available for sale securities	$ 4,706	$ 869