Stockholders' Equity (Details) - USD ($)	6 Months Ended
Jun. 30, 2019	Mar. 31, 2019	Jan. 01, 2019
Equity [Abstract]
Remaining authorized repurchase amount	$ 26,800,000		$ 20,500,000
Share repurchase program, authorized amount		$ 20,000,000.0	$ 60,000,000.0
Common stock repurchased and retired (in shares)	1,074,800
Stock repurchased and retired during period, value	$ 13,700,000

Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration