Consolidated Statements of Stockholders' Equity (Parenthetical)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Common Stock [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock dividend declared	5.00%	4.00%	4.00%

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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