Loans - Outstanding Principal and Carrying Amount of Acquired Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Outstanding principal balance and the carrying amount of loan acquired [Abstract]
Outstanding principal balance	$ 84,832	$ 104,172
Carrying amount	78,635	96,487
Outstanding principal balance and the carrying amount of loan acquired, impaired [Abstract]
Outstanding principal balance	29,648	34,378
Carrying amount	$ 24,860	$ 28,669