Consolidated Statements of Shareholders' Equity (Parenthetical) - $ / shares	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Statement of Stockholders' Equity [Abstract]
Preferred stock, cash dividend (in dollars per share)	$ 80,000,000	$ 80,000,000.00

Aggregate dividends paid during the period for each share of preferred stock outstanding.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration