Stockholders' Equity (Tables)

12 Months Ended

Dec. 31, 2019

Stockholders' Equity Note [Abstract]

Schedule of Weighted Average Number of Shares [Table Text Block]

The following table provides the computation of diluted weighted average number of common shares outstanding:

	Year Ended December 31,
	2019	2018	2017
Computation of diluted weighted average shares outstanding:
Basic weighted average shares outstanding	53,449,834	51,487,557	52,523,272
Incremental shares from assumed exercise of stock options and vesting of restricted stock	1,464,053	1,499,713	1,793,375
Incremental shares from assumed conversion of convertible debentures	—	1,640,477	799,680
Diluted weighted average shares outstanding	54,913,887	54,627,747	55,116,327