Subsequent Events - Preferred Stock Dividend (Details) - Subsequent Event [Member]	May 03, 2018 $ / shares
Subsequent Event [Line Items]
Dividend accrual period on annual basis	360 days
Annual dividend rate (in dollars per share)	$ 1.675
Annualized dividend rate, per 30-day month (in dollars per share)	$ 0.1395833

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

No definition available.

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration