FHLB Borrowings (Details) - Schedule of components of FHLB borrowings and weighted average interest rates - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
By type of borrowing:
FHLB borrowings (in Dollars)	$ 629,979	$ 670,077
Weighted average interest rates	2.32%	1.76%
By remaining period to maturity:
Less than 1 year (in Dollars)	$ 459,979	$ 505,077
Less than 1 year	2.24%	1.59%
1 year through less than 2 years (in Dollars)	$ 25,000	$ 35,000
1 year through less than 2 years	1.85%	1.60%
2 years through less than 3 years (in Dollars)	$ 95,000	$ 85,000
2 years through less than 3 years	2.76%	2.65%
3 years through less than 4 years (in Dollars)	$ 25,000	$ 45,000
3 years through less than 4 years	2.13%	2.15%
4 years through 5 years (in Dollars)	$ 25,000
4 years through 5 years	2.92%