Derivatives (Details 6) - USD ($)	Sep. 30, 2017	Dec. 31, 2016
Derivatives Assets
Total Gross Amounts	$ 80,466,000	$ 83,780,000
Gross Amounts of Contracts Not Subject to Master Netting Arrangements	57,720,000	51,218,000
Gross Amounts of Contracts Subject to Master Netting Arrangements	22,746,000	32,562,000
Gross Amounts Offset on the Consolidated Balance Sheets	0	0
Net Amounts Presented on the Consolidated Balance Sheets	22,746,000	32,562,000
Gross Amounts Not Offset on the Consolidated Balance Sheets
Derivative Amount	(20,240,000)	(20,991,000)
Collateral Received	(2,230,000)	(10,687,000)
Net Amount	276,000	884,000
Cash collateral received	0	8,100,000
Derivatives Liabilities
Total Gross Amounts	90,915,000	82,323,000
Gross Amounts of Contracts Not Subject to Master Netting Arrangements	17,814,000	24,097,000
Gross Amounts of Contracts Subject to Master Netting Arrangements	73,101,000	58,226,000
Gross Amounts Offset on the Consolidated Balance Sheets	0	0
Net Amounts Presented on the Consolidated Balance Sheets	73,101,000	58,226,000
Gross Amounts Not Offset on the Consolidated Balance Sheets
Derivative Amount	(20,240,000)	(20,991,000)
Collateral Posted	(52,851,000)	(36,349,000)
Net Amount	10,000	886,000
Cash collateral posted	$ 18,000,000	$ 170,000