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Represents the amount of paydown on securities.

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No definition available.

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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-Name Accounting Standards Codification
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- Definition

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

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

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This item represents the cost of debt and equity 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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- Definition

The fair value of available-for-sale securities that serve as collateral for borrowings.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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No definition available.

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The cash outflow to acquire debt and equity securities not classified as either held-to-maturity securities or trading securities which would be classified as available-for-sale securities and reported at fair value, with unrealized gains and losses excluded from earnings and reported in a separate component of shareholders' equity.

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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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-Name Accounting Standards Codification
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Securities - Amortized Cost and Fair Value (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Securities Available-for-Sale
Amortized Cost	$ 537,645,000	$ 545,433,000
Gross Unrealized Gains	8,467,000	1,011,000
Gross Unrealized Losses	(4,673,000)	(14,606,000)
Fair Value	541,439,000	531,838,000
Other disclosures
Purchases	343,470,000	210,681,000	$ 196,082,000
Sales	232,462,000.000	306,400,000.000	$ 70,176,000.000
Securities pledged to secure deposits and for other purposes	301,000,000	262,600,000
U.S. Treasury
Securities Available-for-Sale
Amortized Cost	4,002,000
Gross Unrealized Losses	(55,000)
Fair Value	3,947,000
US Treasury and Government
Securities Available-for-Sale
Amortized Cost	13,062,000
Gross Unrealized Gains	8,000
Gross Unrealized Losses	(9,000)
Fair Value	13,061,000
U.S. government agencies
Securities Available-for-Sale
Fair Value	13,061,000
U.S. government agencies mortgage-backed
Securities Available-for-Sale
Amortized Cost	12,372,000	42,511,000
Gross Unrealized Gains	7,000
Gross Unrealized Losses	(165,000)	(977,000)
Fair Value	12,214,000	41,534,000
States and political subdivisions
Securities Available-for-Sale
Amortized Cost	272,240,000	68,718,000
Gross Unrealized Gains	7,116,000	258,000
Gross Unrealized Losses	(1,264,000)	(273,000)
Fair Value	278,092,000	68,703,000
Corporate bonds
Securities Available-for-Sale
Amortized Cost	823,000	10,957,000
Gross Unrealized Gains	21,000	9,000
Gross Unrealized Losses	(11,000)	(336,000)
Fair Value	833,000	10,630,000
Collateralized mortgage obligations
Securities Available-for-Sale
Amortized Cost	66,892,000	174,352,000
Gross Unrealized Gains	202,000	374,000
Gross Unrealized Losses	(1,155,000)	(3,799,000)
Fair Value	65,939,000	170,927,000
Asset-backed securities
Securities Available-for-Sale
Amortized Cost	113,983,000	146,391,000
Gross Unrealized Gains	862,000	341,000
Gross Unrealized Losses	(1,913,000)	(8,325,000)
Fair Value	112,932,000	138,407,000
Collateralized loan obligations
Securities Available-for-Sale
Amortized Cost	54,271,000	102,504,000
Gross Unrealized Gains	251,000	29,000
Gross Unrealized Losses	(101,000)	(896,000)
Fair Value	54,421,000	$ 101,637,000
U.S. government agency mortgage-backed
Securities Available-for-Sale
Fair Value	12,214,000
States and political subdivisions & collateralized loan obligations
Other disclosures
Purchases	270,200,000
Sales	146,900,000
Paydown	13,000,000
Talmer
Other disclosures
Decline in securities	9,600,000
Stockholders' Equity \| GCO Education Loan Funding Corp \| Asset-backed securities \| Credit Concentration Risk
Securities Available-for-Sale
Amortized Cost	27,625,000
Fair Value	26,588,000
Stockholders' Equity \| Towd Point Mortgage Trust \| Asset-backed securities \| Credit Concentration Risk
Securities Available-for-Sale
Amortized Cost	29,312,000
Fair Value	29,210,000
Stockholders' Equity \| Student Marketing Association [Member] \| Asset-backed securities \| Credit Concentration Risk
Securities Available-for-Sale
Amortized Cost	25,696,000
Fair Value	$ 25,917,000
Minimum \| Stockholders' Equity \| GCO Education Loan Funding Corp \| Asset-backed securities \| Credit Concentration Risk
Other disclosures
Credit risk as a percentage of benchmark	10.00%
Minimum \| Stockholders' Equity \| Towd Point Mortgage Trust \| Asset-backed securities \| Credit Concentration Risk
Other disclosures
Credit risk as a percentage of benchmark	10.00%
Minimum \| Stockholders' Equity \| Student Marketing Association [Member] \| Asset-backed securities \| Credit Concentration Risk
Other disclosures
Credit risk as a percentage of benchmark	10.00%