Purchased Loans - Changes in Restructured Loans (Details) - Purchased loans $ in Thousands	3 Months Ended
	Mar. 31, 2018 USD ($) loan
Number of Loans
Totals at January 1, 2018 (loans) | loan	68
Additional loans with concessions (loans) | loan	2
Reclassified as performing restructured loan (loan) | loan	1
Paid in full (loans) | loan	(1)
Principal paydowns (loans) | loan	0
Totals at March 30, 2018 (loans) | loan	70
Recorded Investment
Totals at January 1, 2018 | $	$ 8,965
Additional loans with concessions | $	86
Reclassified as performing restructured loan | $	3
Paid in full | $	(76)
Principal paydowns | $	(371)
Totals at March 31, 2018 | $	$ 8,607