Share and Unit-Based Plans - SARs (Details) - Stock Options	6 Months Ended
	Jun. 30, 2019 $ / shares shares
Units
Balance at beginning of period (in shares) | shares	35,565
Granted (in shares) | shares	0
Exercised (in shares) | shares	0
Balance at end of period (in shares) | shares	35,565
Value
Balance at beginning of period (in dollars per share) | $ / shares	$ 57.32
Granted (in dollars per share) | $ / shares	0
Exercised (in dollars per share) | $ / shares	0
Balance at end of period (in dollars per share) | $ / shares	$ 57.32