Investments - Amortized Cost and Fair Value of Securities Available for Sale (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Available for sale:
Amortized Cost	$ 211,406	$ 196,402
Gross Unrealized Gains	929
Gross Unrealized Losses	(3,732)
Mortgage-backed securities	208,603	195,391
Mortgage-backed securities
Available for sale:
Amortized Cost	196,406	196,402
Gross Unrealized Gains	929	1,370
Gross Unrealized Losses	(3,042)	(2,381)
Mortgage-backed securities	194,293	$ 195,391
Utah Housing Corporation bonds
Available for sale:
Amortized Cost	15,000
Gross Unrealized Gains	0
Gross Unrealized Losses	(690)
Mortgage-backed securities	$ 14,310

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

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This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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-Publisher FASB
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Amount of debt securities categorized neither as held-to-maturity nor trading.

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