Securities (Detail Textuals) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Schedule Of Available For Sale and Held To Maturity Securities [Line Items]
Gain on sales of securities	$ 36	$ 106
Proceeds from sale of securities	$ 2,606,000	$ 3,430,000
Percentage of principal outstanding held to maturity securities	85.00%	85.00%
Available-for-sale securities
Schedule Of Available For Sale and Held To Maturity Securities [Line Items]
Gain on sales of securities	$ 24,000	$ 64,000
Held-to-maturity securities
Schedule Of Available For Sale and Held To Maturity Securities [Line Items]
Gain on sales of securities	$ 12,000	$ 42,000

The cash inflow associated with the aggregate amount received by the entity through sale or maturity of marketable securities (held-to-maturity or available-for-sale) during the period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=66010992&loc=d3e26853-111562

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (a),(b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3179-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

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Balance Type:	debit
Period Type:	duration