Purchased Loans - Changes in Restructured Loans (Details) - Purchased loans $ in Thousands	9 Months Ended
	Sep. 30, 2017 USD ($) loan
Number of Loans
Totals at January 1, 2017 (loans) | loan	42
Additional loans with concessions (loans) | loan	31
Reclassified as performing restructured loan (loan) | loan	6
Reclassified as nonperforming (loans) | loan	(8)
Paid in full (loans) | loan	(1)
Charge-offs (loans) | loan	(1)
Principal paydowns (loans) | loan	0
Lapse of concession period (loans) | loan	(1)
Totals at September 30, 2017 (loans) | loan	68
Recorded Investment
Totals at January 1, 2017 | $	$ 4,028
Additional loans with concessions | $	5,182
Reclassified as performing restructured loan | $	534
Reclassified to nonperforming loans | $	(679)
Paid in full | $	(6)
Charge-offs | $	(17)
Principal paydowns | $	(278)
Lapse of concession period | $	(101)
Totals at September 30, 2017 | $	$ 8,663