Accumulated Other Comprehensive Income (Loss) (''AOCI'') - Changes in AOCI by Component (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Changes in AOCI by Component
Balance at the beginning of the period, net of taxes			$ (6,220)
Net current period other comprehensive income (loss), net of taxes	$ 134	$ 1,292	4,212	$ (128)
Balance at the end of the period, net of taxes	(2,008)		(2,008)
Accumulated Other Comprehensive Income / (Loss)
Changes in AOCI by Component
Balance at the beginning of the period, net of taxes	(2,142)	(3,271)	(6,220)	(1,851)
Other comprehensive income (loss) before reclassification, net of taxes	115	1,261	4,496	(223)
Amounts reclassified from other comprehensive income (loss), net of taxes	19	31	(284)	95
Net current period other comprehensive income (loss), net of taxes	134	1,292	4,212	(128)
Balance at the end of the period, net of taxes	(2,008)	(1,979)	(2,008)	(1,979)
Unrealized Gains on Available-for-Sale Securities and I/O Strips
Changes in AOCI by Component
Balance at the beginning of the period, net of taxes	5,170	2,206	1,090	3,666
Other comprehensive income (loss) before reclassification, net of taxes	121	1,273	4,507	(187)
Amounts reclassified from other comprehensive income (loss), net of taxes			(306)
Net current period other comprehensive income (loss), net of taxes	121	1,273	4,201	(187)
Balance at the end of the period, net of taxes	5,291	3,479	5,291	3,479
Unamortized Unrealized Gain on Available-for-Sale Securities Reclassified to Held-to-Maturity
Changes in AOCI by Component
Balance at the beginning of the period, net of taxes	351	419	403	435
Amounts reclassified from other comprehensive income (loss), net of taxes	(8)	(8)	(60)	(24)
Net current period other comprehensive income (loss), net of taxes	(8)	(8)	(60)	(24)
Balance at the end of the period, net of taxes	343	411	343	411
Defined Benefit Pension Plan Items
Changes in AOCI by Component
Balance at the beginning of the period, net of taxes	(7,663)	(5,896)	(7,713)	(5,952)
Other comprehensive income (loss) before reclassification, net of taxes	(6)	(12)	(11)	(36)
Amounts reclassified from other comprehensive income (loss), net of taxes	27	39	82	119
Net current period other comprehensive income (loss), net of taxes	21	27	71	83
Balance at the end of the period, net of taxes	$ (7,642)	$ (5,869)	$ (7,642)	$ (5,869)

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

+ References

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-Name Accounting Standards Codification
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-SubTopic 10
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Amount after tax, before reclassification adjustments, of other comprehensive income (loss), attributable to parent.

+ References

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Amount after tax of reclassification adjustments of other comprehensive income (loss) attributable to parent.

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