Commitments and Contingencies (Corporate Loans) (Details) - Corporate Loan - USD ($)	Sep. 30, 2018	Mar. 31, 2018	Dec. 31, 2016
Other Commitments [Line Items]
Commitment to lend	$ 100,000,000		$ 130,000,000
Amount drawn	$ 60,100,000	$ 124,200,000

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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