Unaudited Quarterly Operating Results (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended																12 Months Ended
	Dec. 31, 2013		Sep. 30, 2013		Jun. 30, 2013		Mar. 31, 2013		Dec. 31, 2012		Sep. 30, 2012		Jun. 30, 2012		Mar. 31, 2012		Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Selected Quarterly Financial Information [Abstract]
Total Revenue	$ 14,949	[1]	$ 14,056	[1]	$ 8,526	[1]	$ 14,760	[1]	$ 13,216	[1]	$ 15,364	[1]	$ 7,727	[1]	$ 10,038	[1]	$ 52,291	[1]	$ 46,345	[1]
Net Income (Loss) attributable to Common Stockholders	1,916		1,752		874		1,113		(826)		2,292		2,084		615		5,655		4,165		4,441
Net Income(Loss), Per Share attributable to Common Stockholders, in dollars per share	$ 0.09	[2]	$ 0.09	[2]	$ 0.04	[2]	$ 0.05	[2]	$ (0.04)	[2]	$ 0.11	[2]	$ 0.10	[2]	$ 0.04	[2]	$ 0.27		$ 0.20		$ 0.22
Reportable Segment
Selected Quarterly Financial Information [Abstract]
Total Revenue																	57,585		50,351		50,979
Segment Profit (Loss)	$ 3,114		$ 3,319		$ 2,244		$ 4,095		$ 3,413		$ 4,658		$ 1,825		$ 3,921		$ 12,772		$ 13,817

[1] Includes investment income and other income.

[2] Net income (loss) per share on a diluted basis. Quarterly rounding of per share amounts can result in a variance from the reported annual amount.