Summary of Significant Accounting Policies (Narrative) (Details) - USD ($)	3 Months Ended					9 Months Ended
	Sep. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Organization Consolidation And Presentation [Line Items]
Cash equivalents	$ 0					$ 0		$ 4,400,000
Repurchases of common stock under share repurchase program (shares)	0		0			100,000	1,000,000.0
Weighted average cost of repurchased shares						$ 16.20	$ 17.11
Repurchases of common stock under share repurchase program		$ 1,416,000		$ 737,000	$ 15,709,000	$ 1,400,000	$ 16,400,000
Share repurchase program authorized	$ 75,000,000.0					75,000,000.0
Remaining under current repurchase authorization	54,200,000					54,200,000
Selling, General and Administrative Expenses [Member]
Organization Consolidation And Presentation [Line Items]
Merger and integration costs	900,000					2,400,000
Accounts Payable [Member]
Organization Consolidation And Presentation [Line Items]
Book Overdraft	$ 19,500,000					$ 19,500,000		$ 2,500,000