Investments (Equity in Earnings (Loss) of Unconsolidated Subsidiaries) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Investments, Debt and Equity Securities [Abstract]
Losses recorded from affordable housing projects	$ 4,661	$ 3,442	$ 14,373	$ 10,713
Tax credits recognized related to affordable housing projects	4,618	4,608	13,855	13,833
Losses from historic tax credit investments	1,394	621	4,776	3,388
Tax credits recognized related to historic tax credit investments	$ 570	$ 1,352	$ 1,925	$ 3,976