Commitments and Contingencies (Narrative and Schedule of Future Minimum Rental Payments for Operating Leases) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Sep. 30, 2012
Commitments and Contingencies Disclosure [Abstract]
2016		$ 1,808
2017		1,611
2018		1,550
2019		1,529
2020		1,577
2021 and thereafter		8,679
Rent expense		2,500	$ 2,500	$ 2,300
Aggregate future minimum lease payments due		16,800
Estimated litigation liability		11,100		$ 21,200	$ 17,500
Change in estimated litigation liability	$ (2,300)
Legal fees paid	$ 7,800
Unfunded commitments to limited partnerships		46,600
Unfunded commitments to secured bank loans		$ 18,700