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Federal Home Loan Bank and Federal Reserve Bank Borrowings | 12 Months Ended
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Dec. 31, 2018
Federal Home Loan Bank and Federal Reserve Bank Borrowings [Abstract] |
Federal Home Loan Bank and Federal Reserve Bank Borrowings [Text Block] | Federal Home Loan Bank and Federal Reserve Bank Borrowings FEDERAL HOME LOAN BANK The Company has entered into borrowing arrangements with the FHLB of Des Moines to borrow funds under a short-term floating rate fed funds overnight advance program and fixed-term loan agreements. All borrowings are secured by stock of the FHLB and a blanket pledge of qualifying loans receivable. The Company had a borrowing capacity with the FHLB of $1.62 billion and $1.43 billion for the years ended December 31, 2018 and 2017, respectively. See Note 5, “Loans,” for the carrying value of pledged loans. At December 31, 2018, FHLB advances were scheduled to mature as follows:
|  | Federal Home Loan Bank Advances Fixed rate advances
|  | Weighted Average Rate |  | Amount
|  | (dollars in thousands)
Within 1 year |  | 2.64 | % |  | $ | 392,000 |
Over 1 through 5 years |  | 3.85 | % |  | 2,000 |
Due after 10 years |  | 5.37 | % |  | 5,000 |
Total |  | 399,000 |
Valuation adjustment from acquisition accounting |  | 523 |
Total |  | $ | 399,523 |
The maximum, average outstanding and year-end balances and average interest rates on advances from the FHLB were as follows for the years ended December 31, 2018, 2017 and 2016:
|  | Years ended December 31,
|  | 2018 |  | 2017 |  | 2016
|  | (dollars in thousands)
Balance at end of period |  | $ | 399,523 |  |  | $ | 11,579 |  |  | $ | 6,493 |
Average balance during period |  | $ | 166,563 |  |  | $ | 79,788 |  |  | $ | 79,673 |
Maximum month-end balance during period |  | $ | 399,523 |  |  | $ | 317,480 |  |  | $ | 250,515 |
Weighted average rate during period |  | 2.29 | % |  | 1.33 | % |  | 0.80 | %
Weighted average rate at December 31 |  | 2.68 | % |  | 4.08 | % |  | 5.42 | %
FEDERAL RESERVE BANK The Company is also eligible to borrow under the FRB’s primary credit program, including the Term Auction Facility auctions. All borrowings are secured by certain pledged available for sale investment securities. While the Company had no borrowings as of December 31, 2018, or at the end of each month in 2018, there were overnight borrowings resulting in average borrowings of $14 thousand for the year. The Company had no borrowings in 2017 or 2016. The Company pledges securities and loans for borrowing capacity at the FRB and had a borrowing capacity with the FRB of $107.1 million and $100.1 million for the years ended December 31, 2018 and 2017, respectively. See Note 4, “Securities,” for the carrying value of pledged investment securities and Note 5, “Loans,” for the carrying value of pledged loans.

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