Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2020

Stock-Based Compensation [Abstract]

Disclosure of Share-based Compensation Arrangements by Share-based Payment Award [Table Text Block]

The following table summarizes our restricted stock award activity for the years ended December 31, 2020, 2019 and 2018. The vesting dates for the awards vested in 2020 occurred relatively evenly throughout the year ended December 31, 2020. The fair value of awards vested during 2020, 2019 and 2018 was $2.3 million, $1.8 million and $0.8 million, respectively.

	2020
	Number of Restricted Stock Awards ( in thousands)	Weighted Average Grant Date Fair Value
Unvested at January 1	52.1	$	20.55
Granted	119.9	20.24
Vested	(111.8)	20.38
Forfeited	(0.5)	19.32
Outstanding (unvested) at end of year	59.7	$	20.29

	2019
	Number of Restricted Stock Awards ( in thousands)	Weighted Average Grant Date Fair Value
Unvested at January 1	26.5	$	21.31
Granted	114.0	19.88
Vested	(87.9)	19.93
Forfeited	(0.5)	17.11
Outstanding (unvested) at end of year	52.1	$	20.55

	2018
	Number of Restricted Stock Awards (in thousands)	Weighted Average Grant Date Fair Value
Unvested at beginning of year	53.7	$	21.82
Granted	10.0	18.58
Vested	(35.7)	21.48
Forfeited	(1.5)	17.11
Outstanding (unvested) at end of year	26.5	$	21.31