Investments: Available-for-sale Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Amortized Cost	$ 250
Amortized Cost	142,219	$ 145,216
Gross Unrealized Gains	1,107	572
Gross Unrealized Losses	(1,745)	(3,618)
Fair Value	141,581	142,170
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Fair Value	250
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Amortized Cost	7,231
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Fair Value	7,279
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost	19,283
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value	19,161
Debt Securities, Available-for-sale, Allocated and Single Maturity Date, Maturity, after 10 Years, Amortized Cost	50,890
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after 10 Years, Fair Value	50,486
Debt Securities, Available-for-sale, Amortized Cost	77,654
Schedule of Available for sale Securities Debt Maturities	77,176
Mortgage backed investments Amortized Cost	64,565
Mortgage-backed Securities Available-for-sale, Fair Value Disclosure	64,405
Mortgage-backed investments, Fannie Mae
Amortized Cost	23,619	24,276
Gross Unrealized Gains	227	24
Gross Unrealized Losses	(130)	(657)
Fair Value	23,716	23,643
Mortgage-backed investments, Freddie Mac
Amortized Cost	6,269	6,351
Gross Unrealized Gains	118	10
Gross Unrealized Losses	0	(74)
Fair Value	6,387	6,287
Mortgage-backed investments, Ginnie Mae
Amortized Cost	22,856	23,311
Gross Unrealized Gains	71	0
Gross Unrealized Losses	(489)	(1,250)
Fair Value	22,438	22,061
Mortgage backed investments other [Member]
Amortized Cost	11,821	8,983
Gross Unrealized Gains	59	17
Gross Unrealized Losses	(16)	(21)
Fair Value	11,864	8,979
Municipal Bonds
Amortized Cost	7,598	10,615
Gross Unrealized Gains	291	49
Gross Unrealized Losses	0	(120)
Fair Value	7,889	10,544
US Government agencies
Amortized Cost	46,565	48,190
Gross Unrealized Gains	54	73
Gross Unrealized Losses	(672)	(825)
Fair Value	45,947	47,438
Corporate Bonds
Amortized Cost	23,491	23,490
Gross Unrealized Gains	287	399
Gross Unrealized Losses	(438)	(671)
Fair Value	$ 23,340	$ 23,218

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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