Benefit Plans Benefit Plans (ESOP) (Narrative) (Details) - USD ($)	12 Months Ended
	Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018	Dec. 31, 2017
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
ESOP, requisite service period	1 year
ESOP, requisite service period (per year)	1000 hours
ESOP, shares purchased to partially fulfill annual discretionary allocation	28,000		60,000
ESOP, vesting period	6 years
ESOP expense	$ 1,100,000		$ 1,100,000
ESOP, number of allocated shares		30,000		60,000
ESOP,cash contributions	$ 539,000	$ 539,000
Minimum
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
ESOP participation age limit	21 years