Restructuring (Details) - USD ($)	3 Months Ended			12 Months Ended
	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2014	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost				$ 0	$ 2,017,000	$ 3,724,000
Restructuring and Related Cost, Cost Incurred to Date				6,400,000
Restructuring Reserve			$ 739,000	337,000	1,977,000	3,305,000
Restructuring Reserve, Settled with Cash				(1,640,000)	(3,345,000)	(1,158,000)
Restructuring and Related Cost, Expected Cost				0
Employee Severance [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost				0	2,017,000	3,434,000
Restructuring Reserve			739,000	337,000	1,977,000	3,305,000
Restructuring Reserve, Settled with Cash				(1,640,000)	(3,345,000)	(868,000)
Other Expense [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost				0	0	290,000
Restructuring Reserve			0	0	0	0
Restructuring Reserve, Settled with Cash				$ 0	$ 0	(290,000)
Banyan Acquisition and WMT Management Restructuring Plan [Member] | Wealth Management and Trust Segment [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	$ 900,000	$ 1,100,000	$ 700,000			$ 3,700,000