Significant Accounting Policies (Policies)	3 Months Ended
Mar. 31, 2015
Accounting Policies [Abstract]
Allowance For Loan Losses [PolicyTextBlock]	Utilization of longer historical loss periods to better reflect the level of incurred losses in the portfolio. Historical charge-off rates are calculated by the Corporation on a quarterly basis by tracking cumulative charge-offs experienced over a two-year loss period on loans according to their internal risk rating (referred to as “base rate” for the quarter). Prior to the second quarter 2014 enhancements, the Corporation would use the base rate of the current quarter or the average of the last 4 quarters, if greater. During the second quarter of 2014, the Corporation eliminated the use of the “greater of” approach and began to use the base rate average of the last 8 quarters. This change captures a longer historical period that helps mitigate period to period volatility in the loss rates. Enhancements of the environmental factors adjustment. Prior to the second quarter of 2014 enhancements, these adjustments were applied in the form of basis point additions to the loss ratio based on changes in credit and economic indicators observed in the most recent periods. Beginning in the second quarter of 2014, the resulting factor derived from a set of risk-based ratings and weights assigned to credit and economic indicators over a reasonable period is applied to a developed expected range of historical losses, in order to adjust the base rates. These enhancements result in a framework that can be applied more consistently, by having a more granular analysis that better captures trends in economic conditions and the impact on the Corporation's portfolio.

Significant Accounting Policies (Policies)

3 Months Ended

Mar. 31, 2015

Allowance For Loan Losses [PolicyTextBlock]

Utilization of longer historical loss periods to better reflect the level of incurred losses in the portfolio. Historical charge-off rates are calculated by the Corporation on a quarterly basis by tracking cumulative charge-offs experienced over a two-year loss period on loans according to their internal risk rating (referred to as “base rate” for the quarter). Prior to the second quarter 2014 enhancements, the Corporation would use the base rate of the current quarter or the average of the last 4 quarters, if greater. During the second quarter of 2014, the Corporation eliminated the use of the “greater of” approach and began to use the base rate average of the last 8 quarters. This change captures a longer historical period that helps mitigate period to period volatility in the loss rates.

Enhancements of the environmental factors adjustment. Prior to the second quarter of 2014 enhancements, these adjustments were applied in the form of basis point additions to the loss ratio based on changes in credit and economic indicators observed in the most recent periods. Beginning in the second quarter of 2014, the resulting factor derived from a set of risk-based ratings and weights assigned to credit and economic indicators over a reasonable period is applied to a developed expected range of historical losses, in order to adjust the base rates. These enhancements result in a framework that can be applied more consistently, by having a more granular analysis that better captures trends in economic conditions and the impact on the Corporation's portfolio.