Stock-based Compensation (Tables)

3 Months Ended

Mar. 31, 2020

Notes Tables

Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity [Table Text Block]

	RSU Awards			PRSU Awards
		Weighted-Average			Weighted-Average
		Grant-Date			Grant-Date
	Shares	Fair Value		Shares	Fair Value
Non-vested at December 31, 2019	428,295	$	24.42	34,186	$	22.38
Granted	170,228		19.79	72,143		20.38
Vested	(232,351)		22.28	(35,149)		20.54
Forfeited	(2,415)		24.62	—		—
Non-vested at March 31, 2020	363,757	$	23.62	71,180	$	21.26
Vested but unissued at March 31, 2020	216,777	$	23.26	62,515	$	21.35

Phantom Share Units (PSUs) [Member]

Notes Tables

Share-based Compensation, Activity [Table Text Block]

Phantom Stock Plan	Shares	Fair Value
Outstanding at December 31, 2019	109,226	$	21.61
Granted	5,798		17.77
Distributions	(26)		20.45
Outstanding at March 31, 2020	114,998	$	13.36
Vested at March 31, 2020	114,627	$	13.36