Summary of Significant Accounting Policies (Income Taxes and Investment in Tax Credit Projects) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Accounting Policies [Abstract]
Contingent income tax liabilities recorded	$ 0	$ 0
Income tax expense attributable to qualified affordable housing projects	2,600,000	1,300,000
Investment in qualified affordable housing projects	29,500,000	21,700,000
Equity method investments	10,900,000	1,700,000
Remaining unfunded equity contributions	16,000,000
Tax benefits in excess of compensation costs on share-based payments	$ (2,240,000)	$ 0	$ 0