Stock-Based Compensation (Narrative) (Details) - $ / shares	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted	223,495	134,257
2004 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Underlying stock option and restricted stock awards available for grant	0
2009 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for issuance	6,250,000
Maximum number of shares may be issued pursuant to stock awards, stock units and other stock-based awards	3,125,000
Maximum number of shares subject to grants to any one individual in any one year	500,000
Underlying stock option and restricted stock awards available for grant	2,447,574
Performance Share Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period, in years	3 years
Granted	118,924	0
Weighted average fair value of stock awards granted	$ 52.09	$ 52.09
Amortization period of fair value of shares, in months	36 months
Performance Share Units [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of target award amount the grantee may earn	0.00%
Performance Share Units [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of target award amount the grantee may earn	200.00%
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted period	3 years
Granted	68,901
Weighted average fair value of stock awards granted	$ 47.10	$ 36.01
Weighted average fair value of stock awards granted	$ 31.05
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, Shares	0
Vesting period, start, in years	1 year
Vesting period, in years	10 years
Stock Options [Member] | Share-based Payment Arrangement, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	33.00%
Stock Options [Member] | Share-based Payment Arrangement, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	33.00%
Stock Options [Member] | Share-based Payment Arrangement, Tranche Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	33.00%
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted	11,952	0
Weighted average fair value of stock awards granted	$ 33.47
Weighted average fair value of stock awards granted
Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted	4,207
Weighted average fair value of stock awards granted	$ 41.58	$ 36.73
Weighted average fair value of stock awards granted	$ 41.58