Loans to Bank Customers Loan Summary (Details) - USD ($) $ in Thousands | 1 Months Ended | 9 Months Ended | 12 Months Ended |
Aug. 31, 2017 | Sep. 30, 2017 | Dec. 31, 2016 |
Accounts, Notes, Loans and Financing Receivable [Line Items] | | | |
Past due 30 days or more | | $ 6 | $ 8 |
Total outstanding loans to bank customers | | $ 20,028 | $ 6,336 |
Percentage of outstanding loans | | 100.00% | 100.00% |
Financing Receivables, 30 to 59 Days Past Due [Member] | | | |
Accounts, Notes, Loans and Financing Receivable [Line Items] | | | |
Past due 30 days or more | | $ 0 | $ 0 |
Percentage of outstanding loans | | 0.00% | 0.00% |
Financing Receivables, 60 to 89 Days Past Due [Member] | | | |
Accounts, Notes, Loans and Financing Receivable [Line Items] | | | |
Past due 30 days or more | | $ 0 | $ 6 |
Percentage of outstanding loans | | 0.00% | 0.10% |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | | | |
Accounts, Notes, Loans and Financing Receivable [Line Items] | | | |
Past due 30 days or more | | $ 6 | $ 2 |
Percentage of outstanding loans | | 0.00% | 0.00% |
Financing Receivables, Past Due [Member] | | | |
Accounts, Notes, Loans and Financing Receivable [Line Items] | | | |
Percentage of outstanding loans | | 0.00% | 0.10% |
Financing Receivables, 1 to 29 Days Past Due [Member] | | | |
Accounts, Notes, Loans and Financing Receivable [Line Items] | | | |
Past due, current | | $ 20,022 | $ 6,328 |
Percentage of outstanding loans | | 100.00% | 99.90% |
Residential Portfolio Segment [Member] | | | |
Accounts, Notes, Loans and Financing Receivable [Line Items] | | | |
Past due 30 days or more | | $ 6 | $ 6 |
Total outstanding loans to bank customers | | 4,317 | 3,724 |
Residential Portfolio Segment [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] | | | |
Accounts, Notes, Loans and Financing Receivable [Line Items] | | | |
Past due 30 days or more | | 0 | 0 |
Residential Portfolio Segment [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] | | | |
Accounts, Notes, Loans and Financing Receivable [Line Items] | | | |
Past due 30 days or more | | 0 | 6 |
Residential Portfolio Segment [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | | | |
Accounts, Notes, Loans and Financing Receivable [Line Items] | | | |
Past due 30 days or more | | 6 | 0 |
Residential Portfolio Segment [Member] | Financing Receivables, 1 to 29 Days Past Due [Member] | | | |
Accounts, Notes, Loans and Financing Receivable [Line Items] | | | |
Past due, current | | 4,311 | 3,718 |
Commercial Portfolio Segment [Member] | | | |
Accounts, Notes, Loans and Financing Receivable [Line Items] | | | |
Past due 30 days or more | | 0 | 0 |
Total outstanding loans to bank customers | | 122 | 366 |
Commercial Portfolio Segment [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] | | | |
Accounts, Notes, Loans and Financing Receivable [Line Items] | | | |
Past due 30 days or more | | 0 | 0 |
Commercial Portfolio Segment [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] | | | |
Accounts, Notes, Loans and Financing Receivable [Line Items] | | | |
Past due 30 days or more | | 0 | 0 |
Commercial Portfolio Segment [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | | | |
Accounts, Notes, Loans and Financing Receivable [Line Items] | | | |
Past due 30 days or more | | 0 | 0 |
Commercial Portfolio Segment [Member] | Financing Receivables, 1 to 29 Days Past Due [Member] | | | |
Accounts, Notes, Loans and Financing Receivable [Line Items] | | | |
Past due, current | | 122 | 366 |
Consumer Portfolio Segment [Member] | | | |
Accounts, Notes, Loans and Financing Receivable [Line Items] | | | |
Past due 30 days or more | | 0 | 2 |
Total outstanding loans to bank customers | | 1,436 | 1,744 |
Consumer Portfolio Segment [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] | | | |
Accounts, Notes, Loans and Financing Receivable [Line Items] | | | |
Past due 30 days or more | | 0 | 0 |
Consumer Portfolio Segment [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] | | | |
Accounts, Notes, Loans and Financing Receivable [Line Items] | | | |
Past due 30 days or more | | 0 | 0 |
Consumer Portfolio Segment [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | | | |
Accounts, Notes, Loans and Financing Receivable [Line Items] | | | |
Past due 30 days or more | | 0 | 2 |
Consumer Portfolio Segment [Member] | Financing Receivables, 1 to 29 Days Past Due [Member] | | | |
Accounts, Notes, Loans and Financing Receivable [Line Items] | | | |
Past due, current | | 1,436 | 1,742 |
Credit Card Receivable [Member] | | | |
Accounts, Notes, Loans and Financing Receivable [Line Items] | | | |
Past due 30 days or more | | 0 | |
Total outstanding loans to bank customers | $ 8,200 | | |
Credit Card Receivable [Member] | Consumer Portfolio Segment [Member] | | | |
Accounts, Notes, Loans and Financing Receivable [Line Items] | | | |
Past due 30 days or more | | | 0 |
Total outstanding loans to bank customers | | 14,153 | 502 |
Credit Card Receivable [Member] | Consumer Portfolio Segment [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] | | | |
Accounts, Notes, Loans and Financing Receivable [Line Items] | | | |
Past due 30 days or more | | 0 | 0 |
Credit Card Receivable [Member] | Consumer Portfolio Segment [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] | | | |
Accounts, Notes, Loans and Financing Receivable [Line Items] | | | |
Past due 30 days or more | | 0 | 0 |
Credit Card Receivable [Member] | Consumer Portfolio Segment [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | | | |
Accounts, Notes, Loans and Financing Receivable [Line Items] | | | |
Past due 30 days or more | | 0 | 0 |
Credit Card Receivable [Member] | Consumer Portfolio Segment [Member] | Financing Receivables, 1 to 29 Days Past Due [Member] | | | |
Accounts, Notes, Loans and Financing Receivable [Line Items] | | | |
Past due, current | | $ 14,153 | $ 502 |
Collateral Pledged [Member] | Credit Card Receivable [Member] | | | |
Accounts, Notes, Loans and Financing Receivable [Line Items] | | | |
Financing receivable acquired | $ 8,100 | | |