Stock-Based Compensation and Equity - Narratives (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Feb. 27, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award
Stock-based compensation expense	$ 4,900,000	$ 3,700,000	$ 9,101,000	$ 11,917,000
Fair value of vested stock			38,400,000
Deferred compensation obligation	37,263,000		37,263,000			$ 35,766,000
Proceed from issuance of stock	$ 88,073,000		$ 391,904,000
Distributions Declared
Dividends declared per share (in dollars per share)	$ 1.034	$ 1.020	$ 2.066	$ 2.035
Common Stock
Share-based Compensation Arrangement by Share-based Payment Award
Shares issued (shares)	1,116,217		5,169,840
Proceed from issuance of stock	$ 1,000		$ 5,000
ATM Program
Share-based Compensation Arrangement by Share-based Payment Award
Common stock maximum offering value	$ 159,200,000		$ 159,200,000		$ 500,000,000.0
ATM Program | Common Stock
Share-based Compensation Arrangement by Share-based Payment Award
Shares issued (shares)	1,116,217		5,169,840	0
Weighted average share price (usd per share)	$ 80.33		$ 77.06
Proceed from issuance of stock	$ 88,300,000		$ 392,100,000
Restricted Stock, RSU, and PSU
Share-based Compensation Arrangement by Share-based Payment Award
Stock-based compensation expense				$ 4,200,000
Long Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award
Fair value assumptions expected dividend rate (percent)			0.00%
Deferred compensation arrangement with individual, common stock reserved for future issuance (shares)	893,713		893,713			867,871
Deferred compensation obligation	$ 37,300,000		$ 37,300,000			$ 35,800,000
Unrecognized stock based compensation expense	$ 28,200,000		$ 28,200,000
Weighted-average remaining term			2 years 1 month 6 days
Long Term Incentive Plan | Minimum
Share-based Compensation Arrangement by Share-based Payment Award
Risk free interest rate (percent)			2.50%
Fair value assumptions expected volatility rate (percent)			15.80%
PSU Awards
Share-based Compensation Arrangement by Share-based Payment Award
Performance period (in years)			3 years
PSU Awards | Minimum
Share-based Compensation Arrangement by Share-based Payment Award
Potential performance return rate for stock awards			0
PSU Awards | Maximum
Share-based Compensation Arrangement by Share-based Payment Award
Potential performance return rate for stock awards			3