Fair Value Option Summary of Corporation's Mortgage Loans Held for Sale (Details) (USD $)			3 Months Ended
	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2014 Mortgage Loans Held For Sale [Member]	Mar. 31, 2013 Mortgage Loans Held For Sale [Member]	Mar. 31, 2014 Mortgage Loans Held For Sale [Member] Cost [Member]	Dec. 31, 2013 Mortgage Loans Held For Sale [Member] Cost [Member]	Mar. 31, 2014 Mortgage Loans Held For Sale [Member] Fair Value	Dec. 31, 2013 Mortgage Loans Held For Sale [Member] Fair Value
Fair Value, Option, Quantitative Disclosures [Line Items]
Loans Held-for-sale, Mortgages	$ 24,417,000	$ 21,351,000			$ 23,941,000	$ 21,172,000	$ 24,417,000	$ 21,351,000
Gain (loss) in fair values of mortgage loans held for sale			$ 300,000	$ 700,000