The sum of the periodic adjustments of the differences between securities' face values and purchase prices that are charged against earnings. This is called accretion if the security was purchased at a discount and amortization if it was purchased at premium. As a noncash item, this element is an adjustment to net income when calculating cash provided by or used in operations using the indirect method.

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-Topic 230
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-Section 45
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This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The cash inflow associated with maturities (principal being due), prepayments and calls (requests of early payments) on securities not classified as either held-to-maturity securities or trading securities which are classified as available-for-sale securities.

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The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Investment Securities and Fair Value Measurements - Sales, Calls and Maturities (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Schedule of Available-for-sale Securities [Line Items]
Gross Realized Gains			$ 1	$ 6
Gross Realized Losses			0	0
Gross Proceeds from Sales			15	10,016
Gross Proceeds from Maturities			10,974	17,112
Accretion (amortization) of discounts and premiums	$ 200	$ 100	500	300
Agency securities
Schedule of Available-for-sale Securities [Line Items]
Gross Realized Gains			1	5
Gross Realized Losses			0	0
Gross Proceeds from Sales			15	3,005
Gross Proceeds from Maturities			1,044	9,557
Corporate bonds
Schedule of Available-for-sale Securities [Line Items]
Gross Realized Gains			0	1
Gross Realized Losses			0	0
Gross Proceeds from Sales			0	5,011
Gross Proceeds from Maturities			7,440	2,480
Treasury bills
Schedule of Available-for-sale Securities [Line Items]
Gross Realized Gains				0
Gross Realized Losses				0
Gross Proceeds from Sales				2,000
Gross Proceeds from Maturities				3,830
Certificates of deposit
Schedule of Available-for-sale Securities [Line Items]
Gross Realized Gains			0	0
Gross Realized Losses			0	0
Gross Proceeds from Sales			0	0
Gross Proceeds from Maturities			$ 2,490	$ 1,245