Stockholders' Equity and Equity Compensation - Summary of Deferred Stock Unit Activity (Details)	3 Months Ended
	Mar. 31, 2018 $ / shares shares
Deferred Stock Units
Outstanding, beginning balance (in shares) | shares	1,428,878
Outstanding, ending balance (in shares) | shares	1,298,406
Weighted Average Award Date Fair Value
Outstanding, beginning balance (in dollars per share) | $ / shares	$ 21.53
Outstanding, ending balance (in dollars per share) | $ / shares	$ 23.19
Deferred Stock Units
Deferred Stock Units
Outstanding, beginning balance (in shares) | shares	269,977
Awarded (in shares) | shares	1,900
Distributed (in shares) | shares	(4,568)
Outstanding, ending balance (in shares) | shares	267,309
Weighted Average Award Date Fair Value
Outstanding, beginning balance (in dollars per share) | $ / shares	$ 20.14
Awarded (in dollars per share) | $ / shares	25.40
Distributed (in dollars per share) | $ / shares	22.33
Outstanding, ending balance (in dollars per share) | $ / shares	$ 20.14