Fair Value Measurements - Assets Measured at Estimated Fair Value on Nonrecurring Basis by Fair Value Hierarchy (Detail) (Fair Value, Measurements, Nonrecurring [Member], USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
ASSETS
Loans held for sale	$ 1,300	$ 1,516
Impaired loans	14,483	19,197
Other real estate owned	317	317
Mortgage servicing rights	1,211	1,025
Total Assets	17,311	22,055
Level 1 [Member]
ASSETS
Loans held for sale
Impaired loans
Other real estate owned
Mortgage servicing rights
Total Assets
Level 2 [Member]
ASSETS
Loans held for sale
Impaired loans
Other real estate owned
Mortgage servicing rights
Total Assets
Level 3 [Member]
ASSETS
Loans held for sale	1,300	1,516
Impaired loans	14,483	19,197
Other real estate owned	317	317
Mortgage servicing rights	1,211	1,025
Total Assets	$ 17,311	$ 22,055