Equity - Capital Purchase Program Warrants (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended		6 Months Ended
	Jul. 31, 2019	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Class of Warrant or Right [Line Items]
Warrants outstanding						1,900,000
Treasury Stock, Shares, Acquired		500,000
Treasury Stock, Value, Acquired, Cost Method		$ 27.0
Warrant [Member]
Class of Warrant or Right [Line Items]
Warrants Exercised		1,000,000.0	100,000	1,900,000	100,000
Subsequent Event [Member]
Class of Warrant or Right [Line Items]
Treasury Stock, Shares, Acquired	0.3
Treasury Stock, Value, Acquired, Cost Method	$ 16.0