Basis of Presentation and Significant Accounting Policies - Income Statement (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Feb. 01, 2018
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenues	$ 291,490	$ 269,930	$ 796,325	$ 719,814
Operating expenses	180,322	176,835	529,974	494,777
Income before income taxes	102,443	83,743	232,928	194,436
Income tax expense	22,484	26,554	48,044	62,293
Net income	$ 79,959	$ 57,189	$ 184,884	$ 132,143
Diluted earnings per share (in dollars per share)		$ 1.01		$ 2.33
WoodSpring
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Business acquisition, percentage of voting interests acquired					100.00%
As Previously Reported
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenues		$ 295,088		$ 769,785
Operating expenses		217,222		561,906
Income before income taxes		68,514		177,278
Income tax expense		20,919		55,944
Net income		$ 47,595		$ 121,334
Diluted earnings per share (in dollars per share)		$ 0.84		$ 2.14
Adoption of Topic 606 | Accounting Standards Update 2014-09
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenues		$ (25,158)		$ (49,971)
Operating expenses		(40,387)		(67,129)
Income before income taxes		15,229		17,158
Income tax expense		5,635		6,349
Net income		$ 9,594		$ 10,809
Diluted earnings per share (in dollars per share)		$ 0.17		$ 0.19