Other Comprehensive Income (Loss) (Reclassification Adjustments Out of Accumulated Other Comprehensive Income) (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015		Jun. 30, 2014
Unrealized gains/(losses) on investments available-for-sale Affected line item in the Statements of Income:
Investment securities gains	$ 19	$ 0	$ 19		$ 0
Income before taxes			19		0
Tax expense			8		0
Net income			11		0
Amortization of defined benefit pension plan items Affected line item in the Statements of Income:
Recognition of unrealized gain (loss)	$ 259	$ 68	551	[1]	116	[1]
Income before taxes			551		116
Tax expense			220		61
Net income			$ 331		$ 55

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