Commitments and Contingencies (Corporate Loans) (Details) - Corporate Loan - USD ($) $ in Millions	Jun. 30, 2019	Mar. 31, 2018	Dec. 31, 2016
Other Commitments [Line Items]
Commitment to lend	$ 100.0		$ 130.0
Amount drawn	$ 63.8	$ 124.2

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.

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