Liability for Loans Sold (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2018	Dec. 31, 2017
Period after origination for an event of default that may require loan repurchase or reimbursement	90 days
Period after breach of contractual representations or warranties made at the time of sale that are not remedied after the Company receives notice that may require possible loan repurchase or loan reimbursement	90 days
The period after origination for profit refund if the borrower pays off loan	120 days
Other liabilities
Liability for loans sold	$ 2.0	$ 2.1